My bang-for-the buck history goes 3dfx banshee, 3dfx 3000, Radeon 9000, Nvidia 5850 (free, Quakecon 2003), ATI 2900 (free, given), Nvidia 9600 GSO(free, Lanparty), ATI 4850, Nvidia GTX465(free, PDXLAN), Back to the 4850, ATI 6870 CFX(free, PDXLAN), Now ATI 7970.
Wow... I really didn't know how many cards I got free or won in my past... but that's stretching back to damn near '96.
Anyway, the point is Use whatever kicks ass (all except the 2900, that thing was a dog.) Even the 5950 Was proven to kick ass when Doom 3 came out, unfortunately Half-Life 2 was a bigger game. But enough with this trip down memory lane.
The 7970 isn't underclocked. It's comes from ATI with a reference clock of 925. Yes, people hit 1100, 1200, even 1300 on the core doesn't mean thats what every card can do. We also don't know squat diddly about what Nvidia's new cards can do.
Things I've heard...
The 680 GTX is the GK104 core, not the GK110 core. No the 660 TI will walk over the 7970 with a GK104 core and it has a ramped up physics engine, but only on TWIMTBP* games.
850 core with 1700 hotclocked shaders (anywhere between 1024 and 1536) and now 1 Ghz core with no hotclocked shaders.
512Bit 5Ghz 2GB DDR5, no 384 bit and 5.5Ghz 3GB DDR5, no 256 bit 6Ghz 2GB DDR5.
Look... it's potentially better than the 7970... its newer... it should be. I want to know...
A) Is it cheaper than a 7970?
B) Can it run cooler than it??
C) Can it overclock faster than it?
D) Can it do a 32-bit integer right rotate operation in one clock tick?(reference)
E) Will a dual chip card be available (which would allow more than 8 GPU's to be driven in a system.)
Which, I think, is what we're all hoping for... more or less.