Start with a clean baseline
Test each user-facing subsystem independently—display, keyboard/pointer, camera, microphones, speakers, connectivity and battery-visible state—before running invasive OS repair or replacing the main device.
Live evidence
Relevant checks
Dead Pixel TestShow solid colors full-screen so you can visually inspect for dead or stuck pixels.
→Keyboard TestPress keys and verify that the browser receives the expected keyboard events.
→Mouse Button TestVerify left, right, middle, and extra mouse button events.
→Webcam TestOpen your webcam locally to verify that the browser can access and display a live camera stream.
→Microphone TestCheck whether your browser can detect your microphone and receive live audio.
→Left Right Speaker TestPlay left and right channel tones separately.
→Screen Resolution TestShow browser viewport, screen dimensions, and device pixel ratio.
→First sequence
Do the high-signal checks before risky changes
- 1
Run the used/new laptop guided check
- 2
Record which components fail independently
- 3
Use the exact manufacturer's diagnostics for protected internal hardware
Decision points
What the result should change
If a component works in deviceok but one app failsKeep the diagnosis at the app/permission/routing layer.
If a component fails in the browser and the os/oem testMove toward driver/firmware, cable/module or service diagnosis.
If several unrelated components fail togetherLook for a shared dock, USB bus, power, recent update or physical event.
Browser can help check
- Test common user-facing input/output components
- Display visual screen patterns
- Check browser-visible camera and microphone paths
Browser cannot prove
- Read SSD SMART health or RAM faults generically
- Measure battery-cell health universally
- Test every USB-C charging/Thunderbolt electrical path
Repair boundary
Know when to stop browser troubleshooting
- Battery swelling, liquid exposure, burning smell or abnormal heat needs physical service—not stress testing.
- Browser battery/status APIs do not provide manufacturer battery-health metrics.
- BIOS/firmware updates should come only from the OEM and should not be interrupted.
Used-device inspection
What to verify before paying or signing off a repair
- Full-screen display/pixel inspection
- Every key, pointer/trackpad, camera, microphone and speaker
- Ports, charger, battery-health screen and sleep/wake behavior