How to Check a Used Laptop Before Buying
What to actually test on a used laptop before you buy it — specs, screen, battery health, and keyboard.
A laptop that boots up and looks clean can still be hiding a swollen battery, a dying hard drive, or a screen with a fault that only shows up under certain conditions. Here's what's worth checking before you hand over money.
Look at the outside first
Check the hinges for looseness — a laptop that's been dropped often shows it there first, even if the screen looks fine. Press gently on the bottom case; if it flexes or bulges anywhere, the battery underneath may be swollen, which is a real safety issue, not just cosmetic. Check the charging port for looseness by wiggling the cable while it's plugged in.
Check the actual specs, not just what the seller tells you
On Windows, right-click the Start button and open System, or search "About your PC," to see the real processor, RAM, and Windows edition. Open Task Manager's Performance tab to see the actual storage type and size — some sellers advertise a laptop as having an SSD when it's actually been fitted with a slower one than claimed, or advertise more RAM than is actually installed.
Run the screen through its paces
Open a plain white image or a blank document full-screen, then a plain black one. Dead pixels show up clearly against white; screen bleed and uneven backlighting show up against black, especially near the edges and corners. Tilt the screen back and forth to check for any flickering or discoloration that only appears at certain angles — a common sign of a loose display cable.
Test the keyboard and trackpad properly
Open a text editor and type every key at least once, including function keys and any keys along the edges that get less use and can go unnoticed as faulty. Test the trackpad's click, right-click, and two-finger scroll.
Check battery health, not just battery percentage
On Windows, run powercfg /batteryreport from the Command Prompt and open the HTML report it generates — this shows the battery's current full charge capacity against its original design capacity, which is a far more honest number than the percentage shown in the corner of the screen. On a Mac, hold Option and click the Apple menu, then System Information, and look under Power for cycle count and condition.
Let it run for a while before you decide
A laptop that's been sitting off for a week can seem fine for the first ten minutes and then start throttling, freezing, or shutting down once it warms up. If you can, use it for a genuine 20–30 minutes — open several tabs, play a video, let the fan kick in — before making your final decision. Buying through Vaza's checkout keeps a record of the transaction and the listing's description, which matters if something you couldn't test in a short viewing turns out to be a real fault.
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