Computer: Nvidia XFX 780i 3-way SLI  64 bit mother board, Core 2 duo E8500 extreme processor, 2 x Geforce  XFX 9600 GSO 768mb VIDEO cards 8gb ram, 4 x 2gb Corsair XMS2 8500 series, 1 Maxtor 250 gb hard drive, 1 Seagate 1.5 tb hard drive, 1 LG blu-ray burner, 1 LG BD-ROM, 1 Cooler Master 650 watt POWER supply, in a Thermal take tower.    If I get mouse freeze, or online video freeze and have to push the restart button for any reason, 95% of the time the operating system is compromised! XP Pro x 64 service pack 2 or Win 7 x 64 home premium. With XP, a reinstall/repair brings it back okay. Win 7 start-up repair doesn't repair it, thus having to format the hard drive and do a clean install. I'm having to do this this almost on a daily basis, if I want to use my computer. If there is a hardware problem, how do I diagnose it? I updated the BIOS, but it didn't seem to help. Can anybody help with this nightmare? I sure would APPRECIATE it.       Thank you David Bradley                                                               Well, not an easy answer. The XP 64 bit was a oddball OS that only a few had.
From personal experience with the standard 32 bit XP. I know that you can put it on a drive and then install Windows 7. But even so, it has drawbacks. The best option is to have to separate hard drives.
There is reason to think that the XP 64 bit will ruin the Win7 64 bit boot loader. If you have to do any kind of repair that writes to the boot area of the hard drive. XP overwrites some information needed by Windows 7. This is because XP is not aware that Windows 7 defines the boot are stuff a bit differently.  Which is is enough reason to want two hard drives.
That is all I can think  of now. Sounds like the 64 bit drivers are not installed properly in each OS...it does make a difference.
If that's not the case then it's most likely a hardware not an OS issue...Operating systems are on separate hard drives. How do I troubleshoot a hardware issue???You can have two or more OS on a PC with separate physical hard drives. The BIOS has a boot MENU for mufti boot installations.
Most modern Desktop motherboards allow:

• Boot from floppy drive.
• Boot from CD/DVD drive.
• Boot from USB device.
• Boot from network.
• Boot from first HDD.
• Boot from second HD.