Boot Problem - W7x64 Stuck At Green Progress Bar, XP OK

I'm having a Windows 7 x64 boot problem that has me stumped. My system is per my profile. I have a dual boot (Windows 7 64 bit and XP 32 bit) system that has been working flawlessly for about 3 months but now, after rebooting into Windows 7 for the first time in a couple weeks, I can't get past the green progress bar loading screen. Nothing else has changed. At first I would have thought it was a run of the mill driver issue but it goes beyond that.

This is from an initial build a couple of years ago (cpu, mobo, etc) but rebuilt with new ram, hdds and OS install week of 1/18/10.

I found a thread here [http://www.sevenforums.com/crashes-debugging/79498-bootup-bsod-cpu-failure.html] with a similar problem but my problem is a little different (dual boot, no BSOD) so I'm starting a new thread.

Here's what I have done:

1) XP (32 bit) boots fine
2) Windows 7 x64 hangs at green progress bar screen
3) W7 safe mode (F8) hangs while loading drivers
4) W7 boot from original DVD hangs at green progress bar screen
5) XP (32 bit) still boots fine

I also noticed bootup through POST seems slower than before but that could be my imagination.

No BSOD for me. My first thought was that since it will not boot from either the installed W7 OS nor the DVD then the problem wasn't the installation but instead hardware or a driver.

Since XP is only accessing the first 4GB or so of my 8GB of ram I thought it might be a bad chip, but running Memtest86+ showed the ram was fine (similar to the other thread). Running in safe mode didn't help with potential driver problems.

Would it help to start pulling out ram, PCI/PCIe cards (sound, video, SATA II controller card) and USB attached hardware? Based on the other thread, I'm guessing not. Any other thoughts?

Thanks,

Don

Disconnect all USB devices and try again.

You might want to pull most of your RAM if that doesn't work.