The Inquirer had a chance to take the cooler off one of the Geforce 8800 GTS 320MB cards and do some basic benchmarketing. The card they tested worked at 500MHz core and 1600MHz memory but some manufacturers might have the faster clocks. Here's some info:

Good morning America, let me introduce the Geforce 8800 GTS 320MB. The card has the good old G80 chip with its small external I/O chip that couldn't fit on the G80 die. The company uses Hynix memory hy5as573225a that can work at 320 Mbit. It specs say it's 256-bit memory at 1.4ns and of course GDDR3 flavoured but it works just fine with this card.

Instead of twelve memory chips the card has ten of them. Ten times thirty two gives you 320MB of memory. The card scores 28000 in 3Dmark03, 15000 at 3Dmark05 and 8800 in 3Dmark06. In games it pulls more than 100 FPS at 16x12. It looks fast to me.