I remembered Lan Gear Infinity a week ago, but not sure how easy it is to source (will be from abroad).
Which card specifically were you wanting to use?
I've had the SG05 450w for months now and never had a single problem, best mini-itx case until the SG08 imo
But you need the better cooling of the SG05 with a decent graphics card in it... plus it's cheaper. You can get the 450w version for £91!
have seen the 300w today only - shame they haven't done the 450w version on that any time recently.
Think may be pushing it with the 300w using 15 2500k , hd6870 , ssd and 1tb sata