I read somewhere that the 8800GT's core cannot make full use of the 1gb though I have no way of knowing if this is true. Even if it can you'd need a 30"+ monitor to really make use of the extra mem.
I'd go for a Plain 8800GT and OC yourself. EVGA is supposed to be really good, but I have no personal experience with them.
This HardOCP article states that the extra mem adds next to nothing in the performance department, however, if you don't care or aren't subject to the great warranty other brands (like evga and XFX) offer I really recommend getting the palit 512 MB Sonic version, as it has a better cooling solution in both performance and noise levels and will OC past most of the other brands, for example, the guys at hardOCP (And I) got the card to 740 core and around 1000 MHZ mem, toms tried a leadteck and got to 680/1050, http://www.tomshardware.com/2007/1 [...] rclocking), the guys at firing squad got 694/980 using a reference sample (or an EVGA, not sure) (http://www.firingsquad.com/hardware/nvidia_geforce_8800_gt_performance/page18.asp) and so on, more reviews for you here (http://forums.anandtech.com/messageview.aspx?catid=31&threadid=2110122)
So, the point is, the palit 512 sonic will be cheaper, have better cooling (and anyone can tell you that the stock cooling sucks in the 8800gt) and OC better, the only dropdown is worse bundle (tomb raider legacy in my case, I've heard EVGA has crysis in it) and worse warranty, if that's not a problem for you, the go for it, in other case then get a more established brand like XFX, eVga or BFG.
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-Life is a fight you can't win.
-That doesn't mean you can give up!!!!
rob is right - over and over high ram has never proven to make any differnce gaming - i wonder why they keek do it?>
LoL I remember when it was argued when I had my 9800 PRO 128MB that anything over 128MB on a v-card was useless. Naturally it took about 3 years before that was a completely different story...but by the time another 3 years roll by and the 1GB of GDDR is useful the architecture of the card would be so outdated it would have a hard time playing the game anyways....
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The computer allows you to make mistakes faster than any other invention, with the possible exception of handguns and tequila- Mitch Ratcliffe