PowerColor 7950 PCS+pictures
I'm not sure what the length of that card is, exactly.
Neither do a few of the members on that board.
The PCB seems to be reference according to this review
The 7950 and the 7970 use the same PCB meaning that most reference cards should fit with very little to absolutely no modification, whatsoever.
If you want a ridiculously short card, look for a truncated version of a 560Ti ( Palit made some good ones ie: the SONIC )
or pick up a 7870 when they launch (Club3D's is VERY short. I'm sure others will follow.)
As for 570's, in addition to the EVGA HD's, there are a few other options out there as well.
Most notably, MSI's TFIII 570 will squeeze in, and might be a great option should you not need more than 1.28GB of VRAM.
The SG05 will accept cards all the way up to just under 10.5" (266mm) assuming the PCI power connectors are facing 'upwards' on the card.
Should they be protruding from the end of the card, look for something just under 10"(around 250mm).
For more information on GPU compatibility, take a full read through this thread
You should leave enlightened.