Symptoms of bad RAM
- Random BSODs (especially MEMORY_MANAGEMENT or PAGE_FAULT_IN_NONPAGED_AREA)
- Application crashes and freezes
- Corrupted files on disk
- PC fails to POST or beeps
Windows Memory Diagnostic
Press Win+R → mdsched → Restart now. Windows runs two passes and reports errors on next boot.
MemTest86
Download from memtest86.com, write to a USB drive, boot it. Run at least 2 full passes — ideally overnight. Any errors = bad RAM.
Isolating the bad stick
Remove all but one stick and run the test. Rotate sticks until the failing one is identified. Test each slot too — a bad DIMM slot on the motherboard can mimic bad RAM.