Does anyone know which sort of DVD drive goes into the mac pro? I wanted to use my pc one but apparently it won't work because it to big. Is there some sort of standard which fits in ther mac pro?
Any 5.25" drive should work I believe. The only caveat would be that little plastic piece on the front of the drive tray. Usually that has to be taken off to let the tray slide out.
...that's the supplied drive, a fairly typical one. Unless there's something REALLY special about yours, I don't see why it wouldn't fit. Take out the carrier from the Mac Pro, and see if it fits. No harm done.
Apple also has a manual up in their support section for the installation (DIY) of a new/replacement optical drive. It doesn't mention removing the front piece of the trays, so I assume it's written only for their supplied drives, but you will need to take off the fascia (an easy task) in order that the tray fit through the slots on the Mac Pro.
That's one of the reason I like apple's drives. The front is all nice and small and black, so it doesn't look all ugly from the front being taken off....