Reboot in safe mode with networking, try updating as many drivers as possible either through windows update or actually going to manufacturers website.

Sorry for not updating this in a while, I have been really busy with some other things. I have since replaced the hard drive and reinstalled the OS and have also changed the power supply. The problem is still happening.

If safe mode stops the issue than you more than likely have a driver conflict. Did you install anything new hardware lately? Something that plugs into USB or firewire?

How about updating drivers like video drivers or the like? If using windows update to update the drivers does not help you may try rolling back to older versions.

You more than likely have some bad or incompatible driver, something like a webcam or printer. Safe mode disables these things so there is no crash. You are going to have to go through things one at a time till you find the bad driver.

Check your event viewer too, look for anything that stands out. That may point you in the right direction. After every reboot from an unexpected shutdown the viewer will log an unexpected shutdown event. Trace back in time from there to see what is starting, trying to start, or crashing.

Have you run a complete diagnostics from safe mode? If not you might try to reseat the ram chips first and run the diagnostic. This will take a while and need some watching as well.

Something on the mobo could of crapped out. Battery could be low too. An IDE/SATA/Raid/RAM channel could have dumped. Bios, or the RAM could of took a hit. Could be numerous things.

If it were a driver problem it would have happened before. A surge started the errors, and he replaced the OS. So I'd say its a hardware failure. You can use one of these PC Motherboard Repair/Troubleshoot Boot-Failure Diagnostic PCI Card - Free Shipping - DealExtreme to check the mobo. Its not just for start up problems.

TJ is right you really need a diagnostic check to see whats up. The good side is pretty much anything can be replaced/upgraded including the mobo! Good luck!

other things to keep in mind, sometimes motherboards don't detect your memory timings correctly. Verify the timings in bios. You can use Memtest 86+ to check the memory, timing problems should also manifest themselves as errors in a memory test.
Memtest86+ - Advanced Memory Diagnostic Tool


You might could also try just setting bios back to factory default, or to "optimized settings"

Sorry if this is hijacking your thread Simon, though while all the computer guru's are here, I have a question I'd like to ask.

My computer was built from mostly 2nd hand parts, apart from some things like the hard drive and RAM. I haven't really had this problem until a few weeks ago, however.

I am running Windows 7 SP1

Sometimes, when you request a shutdown, it'll log everything off, and get to the screen where it'll say "Shutting down", however, it'll just sit there until you turn the power off manually.

That is one issue, irregardless of that, there is another problem I encounter every time I turn my computer on (Which isn't often, luckily, it's always left on).

After turning the computer on, it heads to the POST screen, however, just before memory testing, it'll just sit there and do nothing. If you restart it again, it'll go a little further, but still won't boot properly. The only way I have found to fix it, is to short the clear_CMOS header (I've even added a button to it now, so I can reset it easily).

Since software isn't really involved during POST, it would point to some part of my hardware on it's way out I would think.

However, once the computer has booted properly, everything functions fine.

You might check and see if there are any bios updates for your motherboard. However, I don't think that would have anything to do with the hang at Shutting Down.

I would think that if it only boots with the CMOS reset jumper shorted that you have some incorrect settings in the BIOS. You might look to see if it is automatically detecting settings with bad memory timings or something similar. You might see if turning off quick boot (partial memory test instead of full) fixes the problem as well. Running memtest probably wouldn't be a bad idea either.

As far as it hanging on shutdown, you might check your event viewer to see if there are any timeout errors. Sometimes software can lock up on shutdown and windows will just wait for a finished response from the hung software which usually never comes. You might check to see if you have windows configured to clear the page file on shutdown as well, sometimes that can take a very long time. If your on a secure computer than not clearing the file will make shutdowns faster, usually lots faster. If that doesn't fix the problem you might try disabling boot up programs one at a time until the thing shuts off, I would go into MSconfig and select diagnostic startup only to make sure it is something other than what windows needs to run causing the problem first though.

I still believe Simon's issue is a software problem. The CMOS battery doesn't matter once the computer is running, it just stores BIOS settings when power is off. If an IDE/SATA controller was going bad the problem would appear in safe mode as well, the same with RAM issues. A clean copy of windows won't do much good if you immediately reinstall the bad drivers or P&P hardware as well, so unless we know exactly what he did after the reinstall it could very well be the problem.