System crashes and hangs but why?

[RedDwarf]

I have a DFI Lanparty Ultra B which has been running fine for over 3.5 years. But I am now getting repeated crashes and system hangs on a very regular basis. I have tried several different windows installations with the same result so it is highly unlikely to be windows.

My system is overclocked but the overclock does not seem to matter, a mild overclock (211x9.5)@1.65 volts or 200x12@ tried from 1.8 to 1.85 volts. Both of these have just crashed just after getting into windows. Often the mouse stops and icons respond as if the cursor was there so it is not a reboot, it is more like a voltage problem that I have had when overclocking with not quite enough voltage.

It did run fine for a number of hours earlier on but now, it is totally unusable. I am now using an Asus A7N8X Deluxe which runs perfectly to post this as I could do nothing with the DFI.

I did have MBM dashboard on screen to try and see if the voltages had dropped thinking it might be something to do with my PSU, but they were all fine. When running @2.4GHz when it crashed the +12 showed 11.8volts and the core showed 1.84 volts. The temperatures were fine too. So I am running out of ideas as to why it is doing this. Some months ago I added a TV card and that resulted in crashes like I am getting now, but I took that out thinking the card and my PC did not get along and I put the card in the Asus and that is running fine with no crashes.

It does seem worse very late at night, during the day it seems fine.

Does anyone else have any idea what it might be? Or what I can test?

[nightelf84]

Have you tried clearing CMOS to put everything back to default? And if so, do the crashes still occur?