Check the outside, the screen, the keyboard and the charger first. These take two minutes and catch the most common problems.
- Then run a 3-minute Standard run in the laptop's own browser, plugged in, with the seller present. It shows whether the machine holds its level under sustained load.
- A browser cannot read battery wear, drive health or the exact model, so check those in the operating system's own tools.
- A clean result does not prove the laptop is fault-free. It rules out the large problems a short check can see.
The short answer
Look before you test, test before you pay. Spend two minutes on the body, screen, keys, ports and charger; spend 3 on a stress test in the laptop's browser; and read the battery and storage health from the system's own tools. Walk away from a seller who will not let you do any of it.
Two minutes by hand and eye
None of this needs software, and it is where many faults show first.
- Hinges, corners and the lid: cracks, a loose hinge or a bent lid.
- Screen: a plain white page and a plain black one show dead pixels, bright patches and backlight bleed. The dead pixel test on this site does it full screen.
- Keyboard and touchpad: type every key into a text box; the keyboard test shows which ones register.
- Ports and charger: plug the charger in and confirm the laptop says it is charging. Try a USB stick in each port.
3 minutes under load
Open systemcheck.live in the laptop's own browser, plug it in, and start a Standard run. It runs the processor, memory and graphics in turn for 3 minutes and reports each stage's sustained level and the shape of its curve.
What you are looking for is a machine that finishes every stage and holds its level after the short boost step. A run that stops, a stage that fails to start, or a steep fall after the machine has settled are reasons to ask questions. The report names what a shape is consistent with; it does not diagnose the cause from a browser.
What a browser cannot check
A web page cannot read battery wear, drive health, temperatures or the exact processor model. On Windows, the command powercfg /batteryreport writes a battery report with design and full charge capacity; on a Mac, System Settings shows battery condition. Check the processor and memory in the system's About page against what the listing says.
Step by step
- 01
Inspect the body
Check hinges, corners, lid and ports for damage.
- 02
Check the screen and keys
Show a white and a black screen, and type every key into a text box.
- 03
Confirm charging
Plug in the charger and confirm the laptop reports charging.
- 04
Run a Standard test
Plugged in, run SystemCheck's 3-minute Standard run in the laptop's browser and read each stage's curve.
- 05
Read battery and storage health
Use the operating system's own battery report and storage tools.
Terms used here
Questions
- Is 3 minutes enough to find a fault?
- It is enough to see whether the machine holds its level under sustained load and completes every stage. Intermittent faults can need much longer, which is what the Deep run is for if the seller allows it.
- Should I test on battery?
- Test plugged in first, so the result is not limited by battery power. If battery life matters to you, read the battery report as well; a stress test is not a battery capacity test.