I've just installed 2 512MB sticks of DDR RAM (Crucial Ballistix PC4000) to go with the 2 512MB sticks already in the machine. Games that ran fine before the upgrade now crash quite quickly, so obviously something has gone wrong with the RAM.
I ran a copy of Memtest i had on a bootable CD (v3.2). After 1:14 the tests had ran twice, and I had 16 errors on test 5 (8 on the first test, 8 on the second), and 2 on test 7 (both of these on the first test).
I wrote down some of the numbers in the error details, and I can provide them if needed, but I was hoping that someone could tell me what these errors actually mean, and if it can diagnose exactly where the fault lies.
I intend to test each stick individually soon.
(P.S. All sticks are running at 400)