I am not sure if it is the RAM, I did add a stick, but it is identical type, though I couldn't get the same brand. Thing is, this didn't happen for awhile (years) after I got the memory and memtest seems to have no errors (I know memtest isn't perfect). This problem started happening a lot so I reformatted the computer. It has been fine for a few days although it restarted itself again today once and has since been fine for a couple hours. The system error log shows this message: "The computer has rebooted from a bugcheck. The bugcheck was: 0x1000000a (0x00000004, 0x00000002, 0x00000001, 0x804ff322). A dump was saved in: C:\WINDOWS\Minidump\Mini030308-01.dmp." I have included the only dumpfile I have post reformat, as I have only had 1 restart. Should this ever happen on a normally functioning computer? (Could it be coincidence that this happened?) I am not willing to run this machine with anything less than 1gb of ram. Right now the two slots are filled with 512mb sticks of 2700 i believe. I really just want to figure out what the problem is so I can fix it or forget it. Thanks very much for the help.