you can put 2 on if you use a DPDT switch and an alternate IDE cable (llamma.com has info how to do it) or do what I do, use an xtender, I have 3 , 250gb hdds on my xbox but you can only ever use one at a time, no matter how you do it. Multiple hdds has uses, either for storage, or adding another hdd when you have already made a xbox live subscriptiuon with your original
The way xtender arranged it, you can have as many hdds as you like but there is always only one used at a time. Imagine an xbox with 16 hdd connected. that is idiotic.
I put my xbox in a pc tower and have 3 120 gig hd,and room for 4 more,,,,added more fans and a dvd rom
