Hardware and Network Troubleshooting practice questions

Answer: A) The new router's DHCP gave the printer a different IP address, so the PCs' printer ports point to the old address

Replacing a router usually means a new DHCP scope, so the printer gets a new IP address. PCs that added it by IP now point to a stale address. Update the printer port or re-add the printer, and reserve its address.

• ACorrect. A new router usually has its own DHCP scope, often on a different subnet, so the printer gets a new lease. The PCs still send jobs to the old IP address in their printer port settings, so the printer shows offline. To fix it, update the port or re-add the printer, and give the printer a DHCP reservation or static IP so this doesn't happen again.
• BIncorrect. The printer's display shows it is connected to the SSID, so its wireless radio is working and it has associated with the new router.
• CIncorrect. Wireless clients scan for an SSID on any supported channel in its band, and the printer has already connected. A channel change doesn't explain why PCs can't reach it.
• DIncorrect. A brief network outage doesn't corrupt the Print Spooler service, and it is very unlikely to fail on every PC at the same moment. The thing the PCs have in common is the printer's changed address.

Answer: A) Clogged vents or a failing fan causing a thermal shutdown

Shutdowns that happen only under sustained heavy load point to overheating: compromised cooling lets temperatures reach the critical trip point, and the system shuts down to protect itself. Clean the vents, check the fan, and replace the thermal paste if needed.

• ACorrect. Heavy workloads raise CPU and GPU temperatures. If dust blocks the airflow or the fan is failing, the system reaches its critical temperature trip point and shuts down to protect the hardware. Light use doesn't produce enough heat to reach that point.
• BIncorrect. A weak CMOS battery typically causes lost date and time or reset BIOS/UEFI settings at startup. It doesn't cause load-dependent power-offs while the system is running.
• CIncorrect. Sleep timeouts are triggered by inactivity, not heavy use. A sleeping laptop also resumes normally instead of powering off abruptly in the middle of active gaming.
• DIncorrect. Low disk space can cause slowness, failed updates, or low-memory warnings. It doesn't make the laptop cut power, and it wouldn't affect gaming only while sparing all-day light use.

Answer: A) Toner save or economy mode is enabled in the print driver on the user's PC

The printer's own configuration page prints correctly, so the print engine and supplies are fine. Faded output from only the user's jobs points to a driver setting such as toner save/economy mode on the PC.

• AThe printer's own configuration page prints correctly, so the toner, drum and fuser are working. Only jobs sent from the user's computer come out faded, which points to a host-side driver setting such as toner save or economy mode. That mode deliberately puts down less toner, so text looks light gray.
• BA failing fuser usually causes toner that smears or rubs off because it isn't fused to the paper. It would also affect the configuration page printed from the control panel, and that page printed correctly.
• CA worn drum causes problems such as gray backgrounds, repeating marks or streaks on every page the print engine produces, including the control-panel configuration page. That page printed cleanly, so the drum is unlikely to be the cause.
• DLow toner can cause faded print. But the cartridge reports 80% and the printer's own configuration page is dark, so toner supply is not the problem.

Answer: A) The graphics output's RGB color range (Full 0-255 vs. Limited 16-235)

Gray blacks and washed-out colors that start right after switching to HDMI usually mean a Limited-vs-Full RGB range mismatch. Set the GPU output (or the monitor's HDMI range setting) to Full range.

• AOver HDMI, a GPU may treat the display as a TV and send Limited-range RGB (16-235). A monitor expecting Full range (0-255) then shows grayish blacks, dim whites, and washed-out colors. Setting the output to Full range, or matching the monitor's HDMI range setting, fixes the mismatch. DisplayPort typically uses Full range, which explains why the problem started only after the switch.
• BRefresh rate affects how smooth motion looks and can cause flicker or no signal if set out of range. It does not raise black levels or wash out colors.
• CScaling changes the size of text, icons, and apps on screen. It has no effect on color range, black level, or saturation.
• DA non-native resolution makes the image blurry or fuzzy, not washed out. The stem also says the image is sharp and already at native resolution.

Answer: A) Run a pixel-fixing utility that rapidly flashes colors over the affected pixel

A single pixel stuck on one color, even with no video input, is a panel-level fault. A pixel-fixing utility that rapidly cycles colors is a safe first try before treating the panel as defective.

• AA pixel stuck on one color is often a subpixel stuck in one state. Rapidly cycling colors at that spot can sometimes free it. It is non-destructive and worth trying before a warranty claim, but it won't fix a truly dead pixel.
• BThe pixel still appears in the monitor's own on-screen menu with no video input. That means the fault is in the panel, not the PC's graphics driver.
• CRefresh rate affects the whole screen, for example flicker or smooth motion. It doesn't affect a single pixel that is stuck even without a video signal.
• DA cable fault would affect the whole picture or cause signal loss. It would not stay as one fixed pixel when no input is connected at all.

Answer: A) The duplexing assembly's rollers, guides, and seating in the printer

When only two-sided jobs jam, the fault is in the part of the paper path that only those jobs use: the duplexing assembly. The tray, pickup roller, and fuser are already proven to work by the clean single-sided jobs.

• ACorrect. Two-sided jobs are the only ones that send paper through the duplexing assembly. Since single-sided jobs work, the shared paper path is healthy. Worn or dirty duplex rollers, debris in the duplex guides, or a removable duplexer that isn't fully seated are the likely causes.
• BIncorrect. Every page passes through the fuser, including single-sided pages. A faulty fuser would also cause jams or smearing on single-sided jobs, and those print cleanly.
• CIncorrect. The pickup roller and separation pad feed every sheet from the tray, whether the job is one- or two-sided. Single-sided jobs from the same tray feed fine, so these parts are working.
• DIncorrect. A driver or setting problem usually makes a job print single-sided or fail to send. It doesn't cause a physical paper jam inside the printer every time.

Answer: A) Start in Safe Mode and use Device Manager to roll back the display driver

A black screen right after a GPU driver update points to the driver. Booting into Safe Mode, which uses a basic display driver, lets you roll back or uninstall the new driver in Device Manager.

• AThe problem started right after the driver update, so the new driver is the most likely cause. Safe Mode loads a basic display driver, so the technician can see the screen and use Roll Back Driver (or uninstall the driver) in Device Manager to go back to the previous version.
• BThe display worked until the driver changed, and the system boots and loads the desktop. That points to software, not a loose card or a bad power cable. Physical work is not the right first step here.
• CThe firmware settings did not change, and the video works until Windows loads the new driver. Resetting the BIOS/UEFI settings does nothing to the faulty OS display driver.
• DThe system boots and runs normally apart from the display. Nothing suggests file system corruption, and chkdsk would not remove or revert the graphics driver.

Answer: A) The audio signal is exceeding the amplifier's or speakers' clean headroom, causing clipping

Distortion that appears only near maximum volume points to clipping, where the signal exceeds the amplifier's or speakers' clean headroom. Problems that show up at every volume point elsewhere.

• ACorrect. Distortion that shows up only at or near maximum volume is typical of clipping, where the signal goes beyond what the amplifier or speaker drivers can reproduce cleanly. Lower the maximum level, or turn off any software loudness/boost enhancement that drives the signal too hard.
• BIncorrect. A line-in jack is an input, so the speakers would get no playback signal at all at any volume, rather than clean sound that distorts only at high volume.
• CIncorrect. Both are standard sample rates and Windows resamples between them. A sample-rate setting doesn't produce distortion that appears only at high volume.
• DIncorrect. A faulty or outdated driver that drops samples causes pops or stutters at any volume level. It would not stay clean at low and moderate volume and fail only near maximum.

Answer: A) Install the latest graphics driver from the GPU vendor or through Device Manager

A display that works after a restart but not after waking from sleep has working hardware and a failing wake path, which points to the graphics driver. Updating the driver is the logical first step before replacing the GPU, cable, or monitor.

• ACorrect. Both monitors work after a restart, so the GPU, cables, and monitor are working. The failure happens only when the driver has to bring the second display back after sleep, which points to the display driver. Updating it is a low-cost first step before replacing any hardware.
• BIncorrect. The card drives both displays normally after every restart, so a failed GPU is unlikely. Replacing hardware before trying a simple software fix ignores the order of likely causes.
• CIncorrect. A bad cable would also fail after a restart, but this monitor works every time the system restarts. The symptom happens only when waking from sleep, which doesn't fit a damaged cable.
• DIncorrect. Paging file size affects virtual memory for applications. It doesn't control whether the graphics driver brings a display back after sleep.

Answer: A) The wireless adapter's power-saving settings for battery operation are reducing its performance

A problem that appears only on battery points to power management. Windows can apply more aggressive power saving to the Wi-Fi adapter on battery, so set the adapter's power-saving mode to Maximum Performance or stop Windows from turning the device off.

• APower plans can apply a different wireless adapter Power Saving Mode on battery than when plugged in. The adapter's 'Allow the computer to turn off this device to save power' option can also let Windows power it down. Either one can throttle throughput or cause brief drops only on battery. Setting Power Saving Mode to Maximum Performance or clearing that checkbox usually fixes it.
• BChannel interference depends on the radio environment, not on the laptop's power source. It would also affect the laptop when it is plugged in, and other nearby devices could be affected too.
• CIf the driver could not handle the security protocol, the laptop would fail to connect at all, whether or not it was plugged in. It would not cause a problem that happens only on battery.
• DA worn battery shortens runtime, but it does not throttle the wireless adapter. The Wi-Fi slowdown comes from power-management policy, not from the battery's health.