Windows 7: Freezes on restart

[SId0831]

My Windows 7 keep freezing whenever it restarts. Just as 'Shutting down...' message disappears, screen turns black and nothing happens, not showing POST screen or whatever.
I've been geek for 10+ yrs and I just don't know what's happening.

 

[Route44]

Did you install Windows 7 on this system when it previously ran a different OS?

 

[SId0831]

No, it was clean install.

 

[Route44]

Are you able to boot into Safe Mode?

 

[SId0831]

Yep, everything's fine except that problem..

 

[Route44]

Hmmm, we're probably looking at a driver issue because with Safe Mode only essential drivers are loaded preventing many drivers from engaging.

In Event Viewer or Device Manager are there any warning signs?

 

[SId0831]

Nope... I checked there already... thx anyway

 

[Route44]

Can you give us a list of everything you have done so far?

 

[SId0831]

I checked Event Logs, Device Manager, and I tried cold reboot (that worked), and then I scanned for viruses, cleaned up registry, tried reinstall chipset drivers... and still got same problem.