I was given an old desktop from a place I work because it no longer worked and it was time for them to upgrade anyways. It was easy to determine that the only problem was the HDD was corrupted. I have a new HDD I am going to install but I wanted to check the RAM, since that may have caused the corruption. With all 4 modules installed (2 x 1gb, 2 x 256mb), I ran Memtest 4.10. There was an error on the first pass, zero errors on the second pass. I ran Memtest on each module individually to determine the faulty stick, but all passed on at least two passes....I was hoping the faulty stick would show up. I reinstalled ALL sticks and have been running Memtest for the last 24 hours...no errors on 14 passes. Stupid me for not writing down the first error I received. I'd like to figure out if something is wrong before I go forward and start using the computer. What would you guys do in this case? If I knew what module initially caused the error, I'd automatically replace it....but I only know it was one of the four.