I've had a problem with this PC for some time, I've tried different motherboard, cpu, ram, everything but harddrive(which very well may be the problem) It started when i installed my new 250gb SATA II drive, brand new. Launching almost any program, and at random intervals, my entire machine goes into slow-mo mode. Music plays much slower, and the mouse freezes for 1 second, every 3 seconds or so. The new dual-core cpu i got helped it alot, but it still does it sometimes, the only error i can find is this.

An error was detected on device \Device\Harddisk0\D during a paging operation.
and
The device, \Device\Ide\IdePort2, did not respond within the timeout period.

2 different errors in event viewer, but they come in clusters of 3
1, then the other, then the first one again.

The thing is, D: is a DVD Drive, which has no disk in it, so it shouldnt be DOING anything.

Reformatted, tried new cables, and even a new motherboard. What else is there to do. My HD is brand new, dont want to send her back so soon.