I built this computer six weeks ago and had no problems for a month! The first sign of problems came just before Christmas with random crashes and lock-ups! It appeared to be a video card error and I pursued that avenue for a while, even sent the card back to the manufacturer (with there approval) for replacement. In the meantime, I bought another video card (so that I can SLI them when both get here) of the same manu. and model. I installed it, updated the drivers and all seemed well... For about 2 hrs! Then I got more crashes. I downloaded MEMTEST and found that one of my 512mb RAM cards was showing errors. I moved them to a different slot and tried again... No luck, so I removed one and the errors quit in Memtest. I thought I had the problem! Yesterday, I got this new error (the one in the header), since this one is a new type of error that I have never seen on this system, I thought I would get some help!! The system is: AMD Athlon 64 3500+ Abit A8N-SLI mobo 1GB RAM (Currently using 512MB) eVGA Nvidia 7800GT Video card 80GB SATA HDD DVD/CD ROM combo The error message is: BAD_POOL_CALLER Technical Info: ***STOP: 0x000000c2 (0x00000007, 0x00000cd4, 0x00000000, 0xfb913b78) Any help would be appreciated, as I have reached my level of experience!! I have attached the last four or five minidumps. Keep in mind that the earliest ones may have occurred prior to me removing the bad RAM!