I have the new motherboard installed with the old processor and it runs fine other than it stalls intermittantly during when the Windows 7 operating system is loading. To clarify: It may boot completely once or twice or 3 times and everything works fine but then, when started or restarted it will stall about 10 seconds into the loading sequence after the Windows logo appears on the screen. It seems to stall at the same point every time. At this point the CPU activity indicator light ceases to show any activity. I've tried different BIOS settings for everything that looks to me to be boot related, ran System Restore, ran Windows startup repair utility (which looks to me to be nothing more than System Restore?), scanned with AVG and Malwarebytes (both show no threats detected). Does this sound like a software, BIOS, registry, OS, hardware issue or what? Should I try installing the new Phenom X4 9750 CPU first?