Another review:
http://www.hothardware.com/Articles/NVIDIA_nForce_790i_SLI_Ultra_and_GeForce_9800_GX2/
From THG REVIEW:
Having said this, we do not recommend buying a GeForce 9800 GX2 for those who rarely change graphic cards and want to invest in a very high end card and keep it for a long time. There are times when a card like this should excel, like in higher resolution and with demanding settings, but the 9800 GX2 is barely better than a simple GeForce 8800 Ultra. The blame, just like on the 3870 X2, is on the amount of memory being limited to only 512 MB, a quantity incompatible with the very high resolutions and even more with antialiasing. Numbers speak for themselves, when the 9800 GX2 out performs the 8800 Ultra (with 768 MB) by 29% on average and up to 41% in 2560x1600, activating antialiasing at this resolution shortens the gap to 13%! Yet, in many games, it's the only mode that still isn't smooth and the 9800 GX2 doesn't deliver much.
As i said before, 98xx series arent called a revolution, they are like the big brothers of 88xx series (just like 78xx and 79xx series)
Unfortuantely most sites only tested with 1920x1200 and 2560x1600 i havent seen any 1600x1200 or lower ones
Time to edit the FAQ