RAM Failure
Summary: -
If you see random application crashes, kernel panics, and failures in simple programs that have worked for a long time, it is possible you are experiencing RAM failure.
Symptoms: -
When RAM starts going bad, what you write to an address is not what you get back when you read it later. This causes random corruption of data, programs that crash, and even kernel "oops"es and kernel panics. If it's only a small amount of RAM that is corrupt then few programs will fail, but something will eventually fail when that memory gets used.
Some kernel panics may bring the system to a halt. If they reoccur soon after the system is off for a while you can be more confident it isn't a heat-related issue.
Even small programs may fail if they happen to use the affected memory. If they work once but then fail on a different attempt, this can be a sign of memory failure, since the memory used will be different from run to run.
Diagnosis:-
When a computer is turned on, it goes through what is called a POST (power-on self test) routine. This is a short diagnostic procedure incorporated into the boot sequence by the BIOS manufacture for troubleshooting purposes.
Many times when there is an error in your boot sequence you will receive an on-screen error message. This error was printed by the video card. But, in some cases, the error is detected early in the boot process and the error cannot be received by the video card. The problem may even be caused by the video card or the monitor. This is why the need for beep codes came to be. If there are three short beeps when you turn on your computer, it indicates ram failure.
Once you suspect RAM is failing, I recommend using Memtest86+ (To download Memtest86+ click here Memtest86+). The easiest way to use it is find an Ubuntu CD. One of the options when booting from the CD is to run a memory test. Let it run through at least one entire test suite, such that the Pass column increases to 1. Preferably let it run overnight to get many successful runs.
