QUOTE(bearda @ Apr 21 2006, 09:11 PM)

I did set the Maxtor drive back to cable select after the upgrade before powering on the box. The upgrade itself went fine; the failure came after I tried running Doom3 later. I had actually booted into XBMC before the box died, so I was pretty confident the hard drive copy worked out OK. I did swap back to the original Xbox hard drive just to make sure though (which is what's hooked up right now).
I'm not too sure what you mean switch on the front panel, you ight have some sort of extra harddrware installed I'm not familiar with. Ways I know of to put the chip into reocvery mode are 1) from the XOS, 2) holding down the eject button, and 3) manually flicking the switch on the chip.
As to the recovery disc, download the latest iso version and use Nero to burn an image to disc. You may need to try different disc types until you find one that works. If you can get it to work look for a tute by Dangerously Cheesy, its actually an OS update manual but same thing.
Ok, you had XBMC working fine then it died once you launched Doom3. At this stage was your Maxtor HDD locked?