I'll be the first to admit that some of these results even surprised me. Most notably the differences between the GTX 275 896 and 1798 card. For the most part at the super high resolutions theres very little differences, Sometimes the 275 pulls ahead with memory. But some of the time the higher density memory loses out due to latency.
I'm actually trying to find out if there might be a reasoning for this. Though I speculate 896 megs of memory just isn't terribly limiting right now. And my own testing seems to show this. ((exception being Crysis @ 2560x1600 @ 8xMS)).
Not trying to discourage or persuade anyone from making a choice here. But I this is the first time I have seen tests like this. I am sure with SLI the extra memory will be put it above the 295 setup. But how much is the question.