yup, its the DealExtreme cable. I had problems with it as well, I kept getting Dirty Disc Errors when playing games from the hdd. Switching to an official cable fixed the problem. I can no longer recommend ordering the dealextreme hdd case. Just get a 20GB hdd off eBay. Even a broken one should work, as long as its not broken because the cable is damaged.
Im also now using the cable below, instead of the adapter from cpustuff:
http://www.esatacables.com/detail/index.cfm?nPID=72687you will have to break off one of the plastic tabs around the internal sata connector on this cable, but thats no biggie.
QUOTE(Spegs12 @ Mar 3 2010, 12:51 AM)

You could leave the Esata cable in the 360 HDD enclosure on cut a hole in the back. Then mount the cable facing out the back.
this is what i ultimately ended up doing. i used my dremel to cut a hole in the back of a 360 hdd enclosure that I got from dealextreme. it looks much cleaner.
