Bump!
Yes, there's some difference,
this site gives you extensive info/benchmarks about many 6600/GT cards and compares them with faster ones.
I got mi
6600GT from MSI, after many review reading and it is the best upgrade I have done to my pc, with my ATI AIW 9000 64MB scored 1426 3DMarks03, and with this one it scored 7489...
I can play F.E.A.R. with everything maxed out (except AntiAliasing and textures, only one level down, video memory limited) at 1024 x 768, Call of Duty 2, the same, Need For Speed Underground 2 all maxed out including antialiasing, Prince of Persia SOT at 1600x1200 and AA maxed... darn, didn't realized it had such beautiful graphics!!. All with zero lag... sweet!
Yup, go for 256MB, I didn't go for it because I was on a budget
In short, I think is the best
value for the
money.
Later...
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Memory doesn't noticeably improve performance, but makes games look prettier, more memory means you can load more and higher resolution textures and more effects, like FSAA (full scene anti-aliasing), lights, bumps and many other effects on surfaces. The F.E.A.R. game showed red numbers when I tried to move the texture slider to high on my 128MB card.
Check
this link for details on video memory.
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