Hi guys, had alot of trouble with this for the past few days and its driving me crazy now 21.gif, my pc is a dell dimension 2400. It started when i brought 1gb pc2700 ddr 333mhz ram which the seller has now told me was high density and my motherboard needs low density, not sure if thats true? Anyway after i tried the ram and found out it didnt work i put my old ram back in and it said "windows could not start because of the following file is missing or corrupt \windows\system32\config\system" researched it and tried what was suggested to recover from a corrupted registry, it didnt work so i had to do a fresh install of xp that didnt work, keep on getting files not copied correctly so i tried fresh install again with different xp cds to see if all files could be copied correctly and it didnt work so i got that fed up of it i just skipped them files but i didnt write them down. When windows started i tried sfc /scannow which results in wrong cd error. I dont get the corrupt \windows\system32\config\system message anymore but im sure all the other problems might have something to do with it. I also got the IRQL not less or equal error one or twice. My main problem is the dell audio drivers which when i try to update multimedia audio controller and modem audio device in device manager it says "cannot install this hardware,, the data is invalid" Not sure whats going on here because i have formatted more than 5 times and used these drivers with no problems before. Ive used adaware, ccleaner, avg, trendmicro/bitdefender online scans to check for virus and spyware. I have tried to sort it out myself but im not sure what else i can do thanks for any help of advice, cheers, tr.