Windows 7: Computer stops responding but doesn't freeze or crash

Ok, I don't have a clue what's going on here.

My Windows 7 Home Prem 64bit machine is only stable in Safe Mode.

If I boot normally, I can do anything for about 10 minutes and then the system stops responding. I can still move the mouse, click icons, things even highlight when I hover over them, but nothing happens. Pages say loading forever and never complete. If I try to open task manager, or Ctrl-Alt-Del, or double click anything, nothing happens. The only way to "recover" is to power off an power back on.

Chkdsk reports no problems. MS Security Essentials is up-to-date and has scanned w/o finding anything. Kaspersky rescue disc running in it's native linux found nothing. Combofix found nothing. Malwarebytes found nothing. SFC.exe /scannow doesn't find anything wrong either.

I can't get any sort of event viewer info because I don't think anything is failing that is being caught and registering there.

I'm at my whits' end here. I have a new HDD that I bought some time ago but have never installed. My last resort is to just do a clean install on that new drive and consider the old (current) drive faulty after 4 years. I don't want to do that though if I can just figure out what's causing the behavior and take care of it.

Any help out there?

Thanks,
Adam

Welcome to Seven Forums ahartman

*You may start from step 3 in this tutorial Troubleshooting Steps for Windows 7
*Is your windows up to date? Do you have Service Pack 1 installed?
*Do you use any registry fixing/pc fixing/cleaning programs?

Keep us posted for further suggestions.