My GTX295 has packed up i belive.. It was the duel pcb version..Now i was wondering how 2 of these in sli would compare to my old gtx295? www.newegg.com/Product/Product.aspx?Item=N82E16814130476c
I think it would give you roughly the same amount of performance. You'd be better getting off something like a second hand GTX470, less power draw and always the option of SLIing later on.
The 295 has 2 lots of 240 stream processors. A siongle 275 has 240 stream processors so it's based on two 275s. Obviously the speeds have been lowered slightly so it'll more than likely hover somewhere between two 260s and two 275s. Edit: You'd still have the same amount of VRAM available as it would be 1.7GB mirrored using the 275s.
The Newegg link isn't working for me either but I'll +1 the suggestion to go for a newer DX11 card like the GTX470/480, they're pretty good value for money these days in terms of price/performance, if noise is an issue for you try and pick up one with a non-reference cooler like the MSI Twin Frozr card.
Unless you've already got a spare gtx275; I don't think there's much point spending money on the older tech when a newer, capable card can be had for abit more money.
GTX 295 = pair of slightly lower clocked GTX 275's, at least that's what I read at the time of the 295's release. As for Vram, you'd effectively only been using the same amount of vram as one card gtx275 in sli and not double the amount.