Hi this is my first post so here goes, I've been setting up an old machine for a friend with a brand new hardrive running Windows XP, but every so often the system BSOD's on me. The reason for doing a clean install on a new hardrive was a) the original hardrive was running low on space and b) the old setup had viruses and also BSOD problems but no BSOD error messages were recorded until now. Before installing the new hardrive I thought I would run memtest for a while to see if any problems occurred, as I've had similar problems in the past with BSOD and it was the RAM at fault. No such luck here though memtest ran for 24Hrs without any errors. Next I installed the new hardrive with Windows XP and all of the latest updates which installed without any problem at all. Next I installed antivirus and any other relevant software without a problem no BSOD's yet. I then slaved up the original hardrive (after scanning it for viruses first) to retrieve any personnel documents, music and videos. This was when was my first BSOD happened right in the middle of copying videos over the BSOD error message read IRQL_NOT_LESS_OR_EQUAL. I rebooted the system then continued to copy the remaining files when AVG popped up and said it had found a virus in a file a was trying to copy. So I stopped the copying process and scanned the original slaved drive with AVG and Lavasoft's Ad Aware when it BSOD again the error message read PAGE_FAULT_IN_NONPAGED_AREA. After retrieving as much data as I could from the original hardrive I thought the BSOD could be to do with the original hardrive being faulty. So I then formatted the original hardrive to be used as extra storage which formatted ok and removed it from the system at the next re-boot to see if it cured the BSOD's. It didn't seem to cure the BSOD's as randomly they seem to keep appearing with no apparent trigger, so I now suspect another piece of hardware or driver. Other thing's I've tried already include: Switching the memory from one socket to another. Still BSOD's. Completed the malware and spyware cleaning recommended on this forum. Still BSOD's. Thrown it out the window!! Still BSOD's. Can anyone please help as this is the last problem before the system is complete (or goes in the bin!) . Thanks in advance, Tony.