mygearcheck
Guides

Hardware troubleshooting guides

A test tells you what your hardware is doing. These explain what it means and what to do next, including when the answer is that nothing is wrong.

Every guide here is written around something you can only say after using the tool next to it: what a resting stick value of 0.12 means, why a trackpad reporting itself as a mouse is normal, why a browser cannot measure a polling rate however loudly other sites claim otherwise. Where a figure comes from a specification it is cited, and where it is our own judgement it says so.

Input devices

6 guides
Keyboard key not working: how to tell hardware from software
A key that does nothing is either a dead switch or something intercepting it. Four checks separate the two in about two minutes, starting in your browser.
Pairs with the keyboard test
Controller stick drift: how to test for it and what to do next
An analog stick drifts when it reports movement while you are not touching it. Test it in your browser in thirty seconds, then decide between a fix, a warranty claim and a replacement.
Pairs with the gamepad test
Mouse double-click chatter: what causes it and how to fix it
One click registering as two is switch chatter. Confirm it in your browser, rule out the settings that imitate it, and work through the fixes in order of cost.
Pairs with the mouse test
N-key rollover and ghosting explained, with a test you can run now
Rollover is how many keys your keyboard can report at once. Ghosting is a key you never pressed. Here is the difference, and what a browser test can and cannot prove about either.
Pairs with the keyboard test
event.key vs event.code vs keyCode: which one should you use
Use event.key for what the user typed and event.code for where the key physically is. keyCode is deprecated and its values are inconsistent. Here is how to choose, with a full reference table.
Pairs with the key code viewer
Laptop touchpad not working: eight checks before you call support
Start with the disable shortcut, because it is the answer more often than anything else. Then work through gestures, drivers and the one reading that confuses everybody.
Pairs with the touchpad test

Audio & video

3 guides
Microphone not working in Windows 11: a step-by-step check
Start in the browser, because it tells you in ten seconds whether the microphone reaches your system at all. Then work outward through permissions, device selection and drivers.
Pairs with the microphone test
Webcam shows a black screen: browser, driver and privacy-shutter checks
A black webcam preview has four common causes and they are quick to separate. Start with the physical shutter, because it is the most embarrassing one to miss.
Pairs with the webcam test
Only one speaker works: how to diagnose left, right and balance problems
Test each channel separately before you suspect the hardware. A balance setting, a half-inserted jack and a mono source all produce the same symptom.
Pairs with the speaker test

Display

2 guides
Dead pixel warranty: what is actually covered
Most warranties do not replace a screen for one dead pixel. Here is the standard the thresholds come from, how to find the policy for your model, and what evidence a claim needs.
Pairs with the dead pixel test
How to check a used monitor before you buy it
Six patterns, ten minutes, and a dark room. What each one reveals, what counts as normal, and which faults are worth walking away from.
Pairs with the monitor test

System

1 guide
How to check a second-hand laptop before you buy it
A fifteen-minute checklist you can run from the seller's own browser, covering the keyboard, trackpad, screen, camera, microphone and speakers, with what each result actually proves.
Pairs with the keyboard test

Why these and not others

There is no guide here that only repeats what ten other sites already say. Each one had to contain something that comes out of running the tests: a threshold we chose and explain, a limitation of a browser API, a distinction between two symptoms that look identical from the outside. Where that was not possible, for example a table of pixel warranty thresholds per manufacturer, we left the page unwritten rather than publish figures we could not verify and keep current.

If you find something wrong here, please tell us. Corrections get made and the date at the top of the page changes with them.