CHECK YOUR MEMORY
One of the most frustrating problems is the undiagnosable "general instability". As a rule (and this comes from several years in the tech field) the very first thing I do is rule out RAM as the problem. RAM goes bad. It goes bad often. It goes bad probably more often than any other component in a computer. Bad RAM doesn't always look bad, as it can appear to be working fine but cause the computer to act strange. It can be random and unpredictable.
The best tool for checking RAM is the free Memtest86. You can download a program from
www.memtest86.com that will create a bootable floppy or a bootable CD image (ISO format). Make the disk, boot off of it, and let it run through all seven tests. If you go through all seven tests with zero errors, your RAM is probably good. But if it fails, you will have just saved yourself hours of frustration trying to diagnose a problem that you could have discovered with a quick Memtest.
Contributed by
primesuspect