iTunes for Windows Vista video playback performance issues
Troubleshooting iTunes for Windows Vista video playback performance
Some customers using computers containing NVIDIA nForce Serial ATA (SATA) controllers may experience unexpected behavior when playing videos in iTunes on Windows Vista from a SATA hard drive. iTunes may unexpectedly quit or become unresponsive or the computer may unexpectedly reboot or show a blue screen. Standard IDE hard disks are unaffected by this issue. If your computer contains a standard IDE hard disk, you can copy your video files to that disk and play those copies of the files in iTunes or QuickTime Player. NVIDIA is investigating the issue.
NVIDIA has determined this issue isn't specific to nForce SATA Controllers or its associated drivers. There are no specific performance issues with nForce based motherboards with Apple iTunes. NVIDIA has reported this application issue to Apple iTunes development.