Hi If I could throw this one out to any techy specialists because Im completely foxed!! I am looking at a all in one Desktop PC HP ms215uk for a friend . Heres the issue He was complaining about intermittent lock ups freezing and blue screens. So I said I would have a look. What I noticed that randomly sometimes only after 2 hours the hard drive would make a clicking and wurring noise sometimes then followed by a blue screen and a restart. Convinced by the clicking noise from the hard drive I confidently ordered a replacement and set about installing a fresh copy of windows 7. All went well for a few hrs then BANG exactly the same error again with the new hard drive so a tried another hard drive and yet again the same fault after 2hrs or so ?????? So clearly its NOT the hard drive despite hard drive symptoms ie. clicking whinning etc. So what the hell is it ? some sort of random power issue to the drive from the motherboard ?? sata controller fault ? I am now testing out the ram with no hard drive connected using a boot disc and memtest 86 so far no issues so I am fearing the worst and it looks like a main board problem ? Its a real pig as all symptoms appear to point to the hard drive put clearly it just isnt the case ? Any help or suggestions appreciated.