With the need for only one 5.25 inch bay, I'd say a Shuttle then. The SN26P looks to meet your needs except for one part. It's not qualified for a 6800 Ultra, however it is qualified for a 7800 GT. The 7800 GT seems to be cheeper, and faster then the 6800 Ultra boards out there. Down the road, if you need better performance, the Shuttle will handle a second 7800 GT in SLI mode.