Can anyone help me about memtest86
Memtest86 is an amazing program... I have been using it the last 15+ years, and it has helped fix a lot of computers, here is a quick and dirty tutorial.
1. Create the Memtest86 CD or USB drive and boot to it.
2. If the computer will not boot at all, remove one stick of RAM at a time until it boots. This alone should tell you if you have a bad stick of RAM.
3. Once you get the machine to boot to Memtest86, the software will all run automatically and perform 8 or so tests, and when it is finished, it will say "Pass: 1", instead of "Pass: 0" (mid right of the screen). If there are errors, you will see the errors listed below in the blank space. Anyway, the idea is to get memtest86 to run and pass a test... and you basically swap out your memory modules to try to isolate which one is bad.
4. If the computer still does not boot, it might be a bad power supply or motherboard.
BTW, it can take a while to run all 8 tests... up to an hour, possibly more, depending on how much memory you have, but it is worth it.