Question 1

MS-DOS memory diagnostics: Viewing TSR load order  After attempting to unload a terminate-and-stay-resident (TSR) program, you are warned that other TSRs were loaded afterward. Which DOS command displays current memory allocation and load order of T…

Accepted Answer

Introduction / Context: Classic DOS systems load device drivers and TSRs into conventional or upper memory. Unloading requires reverse order (last in, first out). The right command reveals what is resident and in which order. Given Data / Assumptions: Environment: MS-DOS or DOS mode in early Windows. Goal: list resident programs and drivers with segment addresses and order. Need: a built-in command that shows memory blocks and owners. Concept / Approach: MEM with the /C (Modules) switch lists memory allocation by program name, showing TSRs and drivers in the order they were loaded, along with sizes and memory regions. This is the canonical way to plan safe unloading or reconfiguration. Step-by-Step Solution: Run: MEM /C to display conventional/upper memory with module names.Identify the TSR you attempted to remove and note which modules follow it.Unload in reverse order if supported (or reboot and adjust AUTOEXEC.BAT/CONFIG.SYS).Optionally use MEM /C /P to paginate long output for readability. Verification / Alternative check: Comparing MEM /C output before and after changing CONFIG.SYS/AUTOEXEC.BAT lines shows how load order changes. Third-party tools (e.g., QEMM) corroborate module mapping. Why Other Options Are Wrong: MEM /P: only paginates MEM output; without /C it does not list modules. MEMMAKER: a separate optimizer for memory usage; not a direct listing of current load order. SYS: transfers system files to a disk; unrelated to TSR listing. None of the above: incorrect because MEM /C is valid. Common Pitfalls: Confusing /C with /D (which shows memory in different formats) and assuming TSRs can always be unloaded safely; many cannot. Final Answer: MEM /C

Question 2

First step for a monitor with no display: What should a technician do first?  A user reports a blank monitor. Before complex diagnostics or opening equipment, what is the very first action you should take?

Accepted Answer

Introduction / Context: Effective troubleshooting starts with simple, non-invasive checks. Display problems are frequently caused by loose cables, powered-off monitors, or input-source mismatches rather than internal failures. Given Data / Assumptions: Monitor appears blank or reports “No Signal.” Safety and warranty considerations discourage opening devices prematurely. User may have recently moved equipment or changed cables. Concept / Approach: Follow the “check the obvious first” principle. Confirm AC power, power switch, indicator LEDs, brightness, and that the video cable is firmly seated at both ends and on the correct port. Verify the monitor’s selected input matches the cable (HDMI/DP/VGA). Step-by-Step Solution: Inspect AC power cord and power strip; ensure the monitor is powered on.Verify the video cable connection at the GPU and monitor; reseat if needed.Confirm input selection and that no bent pins/damaged connectors exist.Only after cabling checks should you proceed to reboots and hardware tests. Verification / Alternative check: Swap in a known-good cable or known-good monitor; if the problem persists, escalate to GPU/PC diagnostics. Many “dead monitor” tickets resolve with reseating or correcting inputs. Why Other Options Are Wrong: Probing internal circuitry first is unsafe and unnecessary at this stage. Simply power-cycling the monitor or PC may help but should follow basic cable/power checks. “None of the above” ignores the foundational step of checking connections. Common Pitfalls: Overlooking a disconnected power brick, sleeping monitor, or wrong input source. Always document the initial state and simple corrections. Final Answer: Check its connections to the computer and power source

Question 3

BIOS/CMOS and fixed disk errors: Identify the most plausible cause  A PC reports a “fixed disk error” during startup. Which of the following is the most likely underlying cause to investigate first?

Accepted Answer

Introduction / Context: During POST, the BIOS queries disk parameters stored in CMOS (or autodetected). If these parameters do not match the actual drive, the BIOS may fail to recognize or initialize the disk, yielding “fixed disk” errors. Given Data / Assumptions: Error appears before the operating system loads. Legacy systems may rely on manually entered cylinders/heads/sectors, while newer BIOSes use auto-detect. Battery or user changes could alter CMOS entries. Concept / Approach: First validate BIOS disk detection: ensure correct drive mode (Legacy/IDE/AHCI), boot order, and geometry parameters. If CMOS battery is weak, settings can reset and cause detection failures. Step-by-Step Solution: Enter BIOS setup; check if the disk is detected correctly.If not, run auto-detect or manually input correct parameters for legacy hardware.Confirm data and power cables are secure; reseat as needed.Replace CMOS battery if time/date and settings are unstable. Verification / Alternative check: After correcting BIOS/CMOS settings, the system should pass POST and enumerate the disk. If the error persists, test the drive with vendor tools or swap cables/ports to rule out hardware faults. Why Other Options Are Wrong: Bad RAM: could cause general POST failures but not a specific “fixed disk” message. Slow processor: unrelated to disk detection and would not generate this error. No-CD installed: optical drives are irrelevant to fixed disk initialization. None of the above: incorrect because CMOS settings commonly cause this error. Common Pitfalls: Overlooking SATA mode mismatches (e.g., OS installed under AHCI but BIOS reset to IDE), and ignoring failing CMOS batteries that intermittently lose settings. Final Answer: Incorrect CMOS settings

Question 4

SCSI bus design: What is required at the ends of a SCSI chain?  When installing SCSI devices on a shared bus, which component is used to terminate the bus at each physical end to prevent reflections?

Accepted Answer

Introduction / Context: SCSI (Small Computer System Interface) uses a multi-drop bus. Proper termination at both physical ends is mandatory to prevent signal reflections that corrupt data. Understanding the nature of termination avoids flaky, intermittent behavior. Given Data / Assumptions: Parallel SCSI flavors require end-of-bus termination. Termination may be active or passive but is fundamentally resistive network matching the bus impedance. Some devices have onboard terminators or auto-termination jumpers. Concept / Approach: Termination presents the characteristic impedance to traveling signals so that they are absorbed rather than reflected. Although physical enablers (jumpers, DIP switches) turn termination on/off, the actual electrical element is a resistor network. Step-by-Step Solution: Identify the two physical ends of the SCSI chain (host adapter often at one end).Enable or attach terminators only at those ends.Ensure no mid-bus devices have termination enabled.Verify with host utilities that termination is correct and IDs are unique. Verification / Alternative check: Scopes show reduced ringing and stable data eyes with proper terminators attached; removing them yields reflections and bus errors. Why Other Options Are Wrong: BNC: a connector type used for coaxial networks (e.g., 10BASE2), not SCSI termination itself. Dip switch: a control to enable termination; it is not the terminating component. All of the above: incorrect because only the resistor network is the terminator. Common Pitfalls: Leaving three terminators active (both ends plus a mid-device) or mixing active/passive terminators inappropriately. Always check SCSI standard for the bus type (SE, LVD, HVD). Final Answer: Resistor

Question 5

ESD safety gear: What component inside an anti-static wrist strap protects the user and the device?  An ESD wrist strap connects a technician to ground. What small component is placed in series so you do not become the least-resistance path to groun…

Accepted Answer

Introduction / Context: Wrist straps protect sensitive electronics by slowly discharging static from the body to ground. Safety and device protection require controlling that discharge current rather than shorting the body directly. Given Data / Assumptions: Standard ESD wrist straps include a coiled cord and a snap to a grounded mat or point. The strap must bleed charge safely and protect the wearer if accidental contact with live voltage occurs. We need the in-line element that limits current. Concept / Approach: A high-value series resistor (commonly around 1 megaohm) is embedded in the wrist strap lead. It limits fault current while allowing static charges to equalize gradually, preventing sudden discharges that can damage components. Step-by-Step Solution: Identify requirement: controlled, safe discharge path to ground.Use a high-value resistor in series to limit current to safe microampere levels under normal voltages.Maintain good skin contact and verify strap with an ESD tester periodically.Always connect to a common point ground tied to equipment ground. Verification / Alternative check: Commercial straps specify a built-in 1 MΩ resistor; continuity testers for ESD confirm both lead continuity and resistor value range. Why Other Options Are Wrong: Capacitor: would store charge and can create transients; not used in series for this purpose. Diode: enforces polarity; not a current-limiting bleed element here. Transistor: active device; unnecessary and unsafe for simple grounding. None of the above: incorrect because a resistor is standard. Common Pitfalls: Bypassing the resistor (homemade straps), connecting to floating metal not tied to ground, or neglecting periodic testing. These negate ESD protection and can be hazardous. Final Answer: Resistor

Question 6

Drive letter assignment in DOS/Windows (legacy): Second IDE drive with primary and extended partitions  A system has two IDE hard disks. Each disk contains a primary partition and an extended partition with one logical drive. Which drive letter will…

Accepted Answer

Introduction / Context: Legacy DOS and early Windows assign drive letters in a specific order: floppies (A:, B:), then primary partitions, then logical drives in extended partitions. Understanding this order helps with multibooting and data partition planning. Given Data / Assumptions: Two IDE drives (Disk 0 and Disk 1). Each has one primary partition and one extended partition that contains one logical drive. No removable drives are occupying letters beyond A: and B:. Concept / Approach: Classic letter assignment proceeds as follows: C: goes to the primary partition of the first physical hard drive. Next, the system assigns letters to logical drives in the extended partition of the first drive. Only after finishing those does it assign a letter to the primary partition of the second drive, followed by its logical drives. With one logical on the first drive, D: becomes that logical, so the second drive’s primary gets E:. Step-by-Step Solution: Assign C: → Disk 0 primary partition.Assign D: → Disk 0 logical drive in its extended partition.Assign E: → Disk 1 primary partition (next after Disk 0’s assignments).Assign F: → Disk 1 logical drive in its extended partition. Verification / Alternative check: Booting such a system in DOS/Win9x or Windows setup demonstrates this order; disk management tools show letter assignments reflecting the described precedence rules. Why Other Options Are Wrong: C: is already used by Disk 0 primary. D: is consumed by Disk 0’s logical drive (given there is one). F: belongs to Disk 1’s logical drive after assigning E: to its primary. None of the above: incorrect because E: is correct under the stated assumptions. Common Pitfalls: Assuming all primary partitions get letters before any logical drives. In legacy DOS/Win9x, logical drives on the first disk are lettered before the second disk’s primary. Modern Windows may behave differently when volumes are hidden or using GPT/UEFI, but the classic exam scenario follows the legacy rule. Final Answer: E

Question 7

PC hardware: On a system that uses an Enhanced IDE (EIDE/ATA) controller, where is it best practice to connect an ATAPI/ATA CD-ROM drive so that the hard disk on the primary channel is not slowed by optical-drive PIO operations?

Accepted Answer

Introduction / Context: Choosing the correct connector for an ATA/ATAPI CD-ROM drive in a desktop with an EIDE controller affects system performance and compatibility. Older optical drives often used lower transfer modes than hard drives, so cabling strategy matters. Given Data / Assumptions: EIDE motherboard with two IDE channels: primary and secondary. Hard disk typically configured as Primary Master. Optical drive is an ATAPI device (CD-ROM). Goal is stable operation without degrading HDD throughput. Concept / Approach: Each IDE channel shares bandwidth between two devices. Mixing a slow PIO optical drive with a fast HDD on the same channel can force the controller to a slower timing during simultaneous access. Placing the optical drive on the different channel avoids this contention. Step-by-Step Solution: Identify channels: Primary IDE and Secondary IDE; each supports Master/Slave.Set HDD as Primary Master for fastest boot/storage operations.Place ATAPI CD-ROM as Secondary Master (or Slave) on the secondary IDE.Verify jumpers/cable select and BIOS detection. Verification / Alternative check: Benchmarks show independent-channel transfers (HDD on primary, optical on secondary) prevent the optical's slow PIO/DMA mode from throttling the HDD. Optical drive access during disk operations does not stall HDD as severely when channels are separated. Why Other Options Are Wrong: on the floppy bus: Floppy interface (FDD) uses a different 34-pin controller; optical drives are ATA/ATAPI, not FDD. on the primary IDE: Works, but can degrade HDD performance when shared; not best practice. on the SCSI bus: Only for SCSI optical drives; an ATA CD-ROM is not SCSI. All of the above: Interfaces are not interchangeable; only the correct IDE channel applies. Common Pitfalls: Incorrect master/slave jumper settings, mixing 40-wire and 80-wire cables, and enabling Cable Select without matching cables cause detection issues. Ensure BIOS set to Auto/ATAPI for the optical drive. Final Answer: on the secondary IDE

Question 8

Fundamentals of PC I/O ports: A COM port on a PC refers to which type of interface?

Accepted Answer

Introduction / Context: Legacy PCs expose hardware interfaces with shorthand names. Knowing whether a COM port is serial or parallel helps with cabling, adapters, and configuring peripherals like modems and serial consoles. Given Data / Assumptions: COM1/COM2 are typical labels on IBM-PC compatible systems. Used historically for mice, external modems, and serial terminals. Electrical standard commonly RS-232 (±3 to ±15 V signaling). Concept / Approach: “COM” stands for communication port and denotes an asynchronous serial interface. It transmits data bit-by-bit over a single data line in each direction, unlike parallel ports (LPT) that send multiple bits simultaneously. Step-by-Step Solution: Identify port labels: COMx = serial; LPTx = parallel.Check connector types: DB-9 or DB-25 often indicate RS-232 serial.Transmission characteristics: start/stop bits, parity, baud rate settings. Verification / Alternative check: Loopback tests, terminal programs, or OS device names (e.g., COM1 in DOS/Windows, /dev/ttyS0 in Linux) confirm serial operation with configurable baud and parity parameters. Why Other Options Are Wrong: parallel: That is the LPT port (Centronics/IEEE-1284), not COM. static: Not a recognized PC interface type. multi: Vague; not specific to COM. SCSI: A separate storage/Peripheral bus; unrelated to COM. Common Pitfalls: Confusing DB-25 parallel and DB-25 serial pinouts; never cross-use cables. Voltage levels differ from TTL serial (like UART headers), so level shifters are needed for microcontrollers. Final Answer: serial

Question 9

Power protection for computers: Which option is specifically designed to clamp transient overvoltages and help prevent power surges from damaging equipment?

Accepted Answer

Introduction / Context: Electrical surges and spikes can damage power supplies, storage, and logic boards. Different devices protect against different power problems; selecting the right one minimizes downtime and data loss. Given Data / Assumptions: Concern is transient overvoltage (surges/spikes) on AC mains. Consumer/professional protective devices include surge suppressors and UPS units. Measurement tools (multimeters) do not provide protection. Concept / Approach: A surge suppressor (surge protector) uses components like MOVs (metal-oxide varistors) or TVS diodes to clamp high-voltage transients, diverting surge energy away from loads. It is the primary device for surge protection. UPS units may include surge suppression, but their core purpose is ride-through power during outages and brownouts. Step-by-Step Solution: Identify the hazard: short-duration overvoltage.Choose device intended to clamp overvoltage: surge suppressor.Optionally add UPS for backup power and line conditioning. Verification / Alternative check: Spec sheets list joule rating and let-through voltage for surge strips. Higher joule ratings imply greater energy absorption. A UPS specification emphasizes VA/W capacity and battery runtime; surge ratings are secondary. Why Other Options Are Wrong: Spike protector: Not a standard product term; if meant as a generic, it is redundant with surge suppressor. The precise term is surge suppressor. UPS system: Provides backup and regulation; not primarily a surge protective device. High-grade multi-meter: Measurement only; offers no protection. None of the above: Incorrect because surge suppressors directly address surges. Common Pitfalls: Confusing power conditioning with surge suppression; ignoring proper grounding; overloading multi-outlet strips beyond their rating. Final Answer: Surge suppressor

Question 10

PC storage standards: “Hard cards” (early HDD-on-card solutions) interfaced to the system using which expansion bus specification?

Accepted Answer

Introduction / Context: Before ubiquitous 3.5-inch drives and SATA, some manufacturers integrated a hard disk and controller onto a single expansion card called a “hard card.” Understanding which system bus these cards used is a matter of PC hardware history. Given Data / Assumptions: Desktop IBM-PC/AT era architecture. Common internal buses: ISA (8/16-bit), later PCI (not used for early hard cards). Goal: Identify the bus spec that hosted hard cards. Concept / Approach: Hard cards plugged into the motherboard expansion slots and presented as an integrated controller+drive. The prevalent general-purpose expansion interface at that time was ISA (Industry Standard Architecture), available in 8-bit and 16-bit variants. Step-by-Step Solution: Identify the physical form: full-length expansion card with HDD.Match with motherboard slots: ISA dominated pre-PCI desktops.Therefore, the governing specification is ISA. Verification / Alternative check: Technical manuals and ads from the period list “Hardcard” devices as ISA add-ins compatible with AT-class systems, not PCMCIA (laptop) nor SCSI unless using a separate SCSI controller card. Why Other Options Are Wrong: SCSI: A peripheral interface; a SCSI hard card would still plug into an ISA SCSI adapter, but typical hard cards were self-contained ISA devices. PCMCIA: Laptop credit-card-size standard, irrelevant to desktop hard cards. MFM: A magnetic encoding/drive interface type, not a system bus specification. None of the above: Incorrect because ISA is correct. Common Pitfalls: Confusing storage encoding/drive interfaces (MFM/RLL/IDE) with the motherboard expansion bus; assuming SCSI due to external devices without considering slot form factor. Final Answer: ISA

Question 11

Networking basics: What is the common “language” or set of rules that computers use to communicate reliably over a network?

Accepted Answer

Introduction / Context: When devices exchange data across a network, they must agree on formats, timings, addressing, and error handling. This agreement is codified by protocols that form the foundation of interoperability. Given Data / Assumptions: Networked environment (LAN/WAN/Internet). Multiple layers (physical through application) in the OSI/TCP-IP models. Question asks for the “language” computers use. Concept / Approach: A protocol is a formal set of rules governing data exchange. Examples include TCP/IP for transport and internetworking, HTTP for web, and SMTP for email. Protocols define syntax (data structures), semantics (meaning), and synchronization (timing/state). Step-by-Step Solution: Identify the abstraction: “language” ⇒ rule set for communication.Map to technical term: protocol.Examples validate: TCP, UDP, IP, ARP, HTTP, DNS. Verification / Alternative check: Network analyzers (e.g., Wireshark) decode frames/packets using protocol specifications, confirming that communication relies on shared protocol definitions. Why Other Options Are Wrong: client: Role of a device/application, not a language. adapter: Hardware interface (NIC), not rules of communication. operating systems: Provide services but are not the communication language itself. None of the above: Incorrect because “protocol” is correct. Common Pitfalls: Conflating hardware interfaces and software roles with communication standards; ignoring that multiple protocols can stack to form a complete solution. Final Answer: protocol

Question 12

PC BIOS/CMOS setup: Which hard-drive related values are stored in CMOS setup for legacy systems (prior to automatic LBA detection)?

Accepted Answer

Introduction / Context: Older PCs required manual entry of hard-disk geometry in CMOS setup so the BIOS could address the drive correctly at boot. Understanding which parameters belong in CMOS helps when working with legacy hardware. Given Data / Assumptions: Legacy BIOS with CMOS RAM storing configuration. Hard disk uses CHS parameters or later LBA translation. Modern SMART/free space tracking is OS-level, not CMOS. Concept / Approach: CMOS setup records drive geometry: number of cylinders, heads, sectors per track, and sometimes landing zone and translation mode. These values allow BIOS INT 13h routines to read/write sectors during POST/boot. Step-by-Step Solution: Enter BIOS: define drive type or user type with cylinders, heads, sectors.Save to CMOS so parameters persist across reboots with battery power.During boot, BIOS uses these values to access the MBR and load OS. Verification / Alternative check: Incorrect geometry prevents OS boot or causes data corruption. Autodetect routines in later BIOS versions populate CMOS with LBA-translated values automatically. Why Other Options Are Wrong: IRQ: Interrupt lines for controllers are separate settings; not the drive geometry itself. Free space: Calculated by OS file systems; not stored in CMOS. Virus alert: Optional BIOS feature toggles, unrelated to drive geometry values. None of the above: Incorrect since geometry is stored. Common Pitfalls: Confusing controller settings with disk geometry; removing CMOS battery resets parameters leading to boot failures on legacy systems. Final Answer: size (heads, cylinders, sectors)

Question 13

MS-DOS memory management: Which DOS component is used to emulate Expanded Memory (EMS) on 80386-class PCs by mapping extended memory into EMS pages?

Accepted Answer

Introduction / Context: Classic DOS software sometimes requires Expanded Memory Specification (EMS). On 80386 and later CPUs, EMS can be emulated using protected-mode paging to map extended memory into a 64 KB page frame in conventional memory space. Given Data / Assumptions: System running MS-DOS 5/6 era. Hardware supports 80386 or later with paging. Need EMS for older applications or drivers. Concept / Approach: EMM386.exe is the memory manager that uses the 80386's virtual 8086 mode and paging to simulate EMS from extended memory (XMS). It cooperates with Himem.sys (XMS driver) to allocate extended RAM and create EMS pages. Step-by-Step Solution: Load Himem.sys to access XMS.Load EMM386.exe with appropriate switches (e.g., EMM386 RAM) to create EMS and UMBs.Legacy programs access EMS via INT 67h through the page frame. Verification / Alternative check: MEM /C in DOS shows EMS status. Applications detect available EMS and run accordingly. Removing EMM386 removes EMS emulation while Himem.sys alone provides only XMS. Why Other Options Are Wrong: Himem.sys: Manages extended memory (XMS), not EMS emulation. Mem386.sys: Not a standard DOS memory manager. Ramdrive.sys: Creates a RAM disk; unrelated to EMS. None of the above: Incorrect because EMM386.exe is correct. Common Pitfalls: Confusing EMS and XMS; enabling EMS can reduce available upper memory if not configured carefully; some protected-mode games prefer XMS only. Final Answer: EMM386.exe

Question 14

Classic Mac OS printing: For a Macintosh to print successfully, which essential software component must be present in the System Folder?

Accepted Answer

Introduction / Context: Classic Macintosh systems (pre-OS X) required specific resources in the System Folder to support printers. Understanding the difference between drivers, enablers, and optional utilities is key to troubleshooting print failures. Given Data / Assumptions: System Folder contains Extensions, Control Panels, and printer-related files. Printing relies on a driver that understands the printer's command language (e.g., PostScript, QuickDraw GX). Some models needed additional enablers for certain printers, but the driver is fundamental. Concept / Approach: The printer driver translates the OS print stream into device-specific commands. Without the driver, the OS cannot render pages correctly for the device, regardless of sharing or fonts. Enablers complement drivers for specific models but do not replace them. Step-by-Step Solution: Install the correct printer driver provided by the manufacturer or Apple.Ensure Chooser/Print Center selects the installed driver.Verify optional enablers/PPDs if required for PostScript printers. Verification / Alternative check: Attempting to print without a driver typically yields no device selection or garbage output. With a proper driver, test print completes with expected formatting. Why Other Options Are Wrong: File sharing software: Irrelevant for local printing; used for networking files. A printer enabler: Sometimes necessary but insufficient without the core driver. The Apple Garamond font set: Fonts affect appearance but are not required to enable printing. None of the above: Incorrect because a printer driver is mandatory. Common Pitfalls: Installing the wrong regional driver, missing PPD files for PostScript, or conflicts with extensions causing print spooler issues. Final Answer: A printer driver

Question 15

Printer performance metrics: LaserJet printers are typically rated in pages per minute (ppm). What unit is commonly used to specify the print speed of dot-matrix printers?

Accepted Answer

Introduction / Context: Different printer technologies emphasize different performance characteristics. Laser printers handle pages as raster images (ppm), whereas impact printers like dot-matrix output streams of characters, so their speed is quantified differently. Given Data / Assumptions: Dot-matrix printers are impact devices printing via pins on a moving head. Common use cases: multipart forms, continuous stationery. Throughput depends on draft vs NLQ modes, width, and character set. Concept / Approach: Impact printer performance is traditionally rated in characters per second (cps). This reflects how many monospaced characters the device can print in a second in a specified mode (e.g., 10 cpi draft). Step-by-Step Solution: Identify printer type: dot-matrix (impact).Recall conventional speed metric: cps for impact printers.Select the corresponding option. Verification / Alternative check: Specifications in manuals list 200–500 cps in draft modes for common models, sometimes alongside lpm for line printers, but dot-matrix desktop units emphasize cps. Why Other Options Are Wrong: lines per inch / characters per inch: These describe print density, not speed. lines per sheet: Not a standard specification. None of the above: Incorrect because cps is correct. Common Pitfalls: Confusing cps with cpm (copies per minute for copiers) or with ppm for page printers; mixing density (cpi, lpi) with throughput ratings. Final Answer: characters per second

Question 16

PC troubleshooting at a client site – First step for a computer that is completely dead (worked yesterday) You arrive and the PC shows no lights, no fans, and no beeps. What should be your very first check before proceeding deeper into hardware diag…

Accepted Answer

Introduction / Context: Field technicians are often called to sites where a previously working computer is now completely dead—no LEDs, no fans, and no POST beep. Efficient troubleshooting begins with simple, high-probability checks that isolate whether the problem is external power, the power distribution to the PC, or the internal hardware. Given Data / Assumptions: The computer was reportedly working the day before. On arrival, there are no signs of life: no power LED, no fans spinning, no beeps. Standard office environment with potential power strips, surge protectors, or UPS units in the power path. Concept / Approach: Adopt a “outside-in” diagnostic strategy. Before opening the chassis or swapping components, verify power delivery from the wall to the PC. Human factors (switched-off strips, tripped breakers, loose cords) and facility issues (dead outlets) commonly cause “dead” symptoms. This step is fast, non-invasive, and can resolve many cases immediately. Step-by-Step Solution: Confirm the AC outlet is live: plug in a known-good device or use a tester.Check the entire power path: wall outlet → UPS/surge protector → power cord → PSU rocker switch → front-panel power button.Inspect for tripped breakers, switched-off power strips, loose IEC connector at the PSU, or a failed UPS.Only after confirming good AC availability should you proceed to PSU testing or internal diagnostics. Verification / Alternative check: Use a receptacle tester or multimeter to verify outlet voltage. Bypass intermediary devices (plug PC directly into a known-good outlet) to eliminate UPS or strip faults. If the outlet is confirmed good and still no signs of life, then proceed to PSU jump-start testing or swap with a known-good PSU. Why Other Options Are Wrong: Testing the PSU is useful but should follow confirming AC power. Replacing the CMOS battery will not revive a stone-dead system. Reseating a storage cable is irrelevant when the system has no power at all. “None of the above” ignores the most common external cause. Common Pitfalls: Overlooking a master power switch on the PSU, daisy-chained power strips, or emergency power-off switches in labs. Assuming a UPS guarantees power—its outlet or internal battery may have failed. Final Answer: Check the AC outlet and power path (outlet, power strip, cord, switch) for actual mains power.

Question 17

PC expansion buses – Can an EISA and an MCA device coexist in the same personal computer? Assume a standard desktop platform without custom bridge hardware.

Accepted Answer

Introduction / Context: EISA (Extended ISA) and MCA (Micro Channel Architecture) were competing expansion bus standards from the late 1980s and early 1990s. Understanding their incompatibility is important for supporting legacy systems and for exam-oriented PC hardware knowledge. Given Data / Assumptions: EISA and MCA were implemented on different families of motherboards. No special bridge or adapter is assumed. Goal is to determine whether one PC can natively host both device types. Concept / Approach: MCA (introduced by IBM for PS/2) is architecturally and mechanically distinct from ISA/EISA. EISA extended ISA while remaining backward compatible with ISA cards; MCA was not mechanically or electrically compatible with ISA or EISA. Therefore, mainstream PCs never supported both buses simultaneously on the same motherboard. Step-by-Step Solution: Identify bus families: ISA → EISA and VESA Local Bus evolved from ISA; MCA is a separate lineage.Check compatibility: EISA slots accept EISA/ISA cards; MCA slots accept MCA cards only.Motherboards were produced either for EISA/ISA or for MCA—not both.Hence, a single PC platform cannot host both device types without exotic, nonstandard bridging. Verification / Alternative check: Historical motherboard references and service manuals list EISA or MCA, rarely both. No standard BIOS or chipset provided mixed-bus capability in desktop systems of that era. Why Other Options Are Wrong: Claims about “BIOS bridging,” “dock-station support,” or “reduced speed” do not address electrical/mechanical incompatibilities. Such configurations were not commercially offered for PCs. Common Pitfalls: Confusing MCA with PCI or thinking EISA is simply “faster ISA” that can adapt to MCA slots—mechanical keys and signaling prevent that. Final Answer: False.

Question 18

Environmental compliance – Which PC component requires EPA-compliant disposal? Select the item that typically falls under hazardous waste guidelines and needs special handling.

Accepted Answer

Introduction / Context: Electronics service work must adhere to environmental regulations. Certain components contain hazardous materials and require special disposal methods to protect human health and the environment. Identifying these parts is a core responsibility of technicians and IT asset managers. Given Data / Assumptions: We consider typical desktop/laptop components. EPA (or equivalent local authority) guidelines apply to hazardous materials. We must choose the component that specifically mandates special handling. Concept / Approach: PC batteries (CMOS coin cells, laptop Li-ion packs, UPS batteries) can contain lithium, cobalt compounds, or lead (for sealed lead-acid), and are classified as hazardous. They must be recycled or disposed through approved channels. While motherboards and power supplies should also be recycled as e-waste, the most stringent, clearly regulated item among the options is the battery. Step-by-Step Solution: Identify materials: battery chemistries include Li-ion, NiMH, or lead-acid—regulated waste.Check disposal guidance: do not incinerate; use collection points or certified recyclers.Contrast with keyboard or metal PSU housing, which are not inherently hazardous (though e-waste recycling is recommended).Therefore, the battery requires EPA-compliant disposal. Verification / Alternative check: Review local e-waste laws: batteries are often singled out for separate collection. Many municipalities ban batteries from regular trash due to fire risk and toxic materials. Why Other Options Are Wrong: Keyboards and metal PSUs can be recycled as general e-waste but lack the specific hazardous designation of batteries. Motherboards contain small amounts of heavy metals but are typically processed through e-waste recycling streams; the question emphasizes the component that specifically “requires” EPA handling—battery. Common Pitfalls: Tossing coin cells into general trash; shipping swollen Li-ion packs without proper packaging; ignoring local transport rules for lead-acid batteries. Final Answer: Battery.

Question 19

Power quality and protection – Which device protects against line deficiencies (sags, brownouts, outages)?

Accepted Answer

Introduction / Context: Computers and networking gear are sensitive to line conditions. “Line deficiencies” include sags, brownouts, frequency anomalies, and full outages. Choosing the correct protection device prevents data loss and hardware damage. Given Data / Assumptions: Goal: protect equipment from undervoltage and outages, not just overvoltage spikes. Office/home environment with standard AC mains power. Typical IT loads (PCs, servers, modems/routers). Concept / Approach: A surge protector primarily clamps transient overvoltages (spikes) using MOVs or similar components. It does not supply power during an outage and does little for sustained sags. By contrast, a UPS contains batteries and power conversion stages to maintain output voltage during deficiencies, surviving outages for minutes and bridging to shutdown or generator power. Step-by-Step Solution: Identify risk: brownouts/outages require energy storage.Match device to risk: only a UPS supplies power when input fails.Confirm surge strips cannot correct low voltage or provide runtime.Therefore, select a UPS to protect against line deficiencies. Verification / Alternative check: Line-interactive and online double-conversion UPS models actively regulate output across a range of input voltages and ride through outages. Specifications list transfer times or continuous conversion. Why Other Options Are Wrong: Surge protectors address spikes only. A logic probe is a digital diagnostic tool, and a capacitor across mains is unsafe and ineffective for sags/outages. Common Pitfalls: Assuming a surge strip equals power protection; undersizing UPS capacity; ignoring battery maintenance leading to failed protection when needed. Final Answer: UPS (Uninterruptible Power Supply).

Question 20

Modem fundamentals – The process by which two modems establish a connection and negotiate parameters is called:

Accepted Answer

Introduction / Context: Traditional dial-up and leased-line modems must coordinate before data transfer. This coordination sets modulation type, error correction, and compression. Knowing the correct term helps in configuration and troubleshooting legacy connections still used in specialized systems. Given Data / Assumptions: Two modem endpoints initiate communication over a telephone or serial link. They must agree on a common set of protocols and speeds. Audible tones and sequences are often heard during the process. Concept / Approach: “Handshaking” is the standard term for the exchange of tones and signals that establish the link configuration. During handshaking, modems negotiate line rates, fallback mechanisms, error-correction (e.g., V.42), and compression (e.g., V.42bis, MNP5). Successful handshaking transitions the connection to a data mode with agreed parameters. Step-by-Step Solution: Call is established; modems detect carrier.Exchange of training sequences and tones occurs.Parameters are negotiated; modems agree on speed/coding.Session enters steady-state data mode following successful handshaking. Verification / Alternative check: Modem logs and AT command responses show negotiation details (e.g., CONNECT 33600/ARQ). Diagnostic LEDs indicate carrier detect and data set ready after handshake. Why Other Options Are Wrong: “Connecting” and “linking” are generic verbs, not the technical term. “Interacting” is vague. “Pinging” refers to ICMP echo on IP networks, unrelated to modem training sequences. Common Pitfalls: Misinterpreting handshake failures as line faults when protocol mismatch or poor SNR is the cause; forgetting to disable call-waiting which interrupts handshakes. Final Answer: Handshaking.

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