GTX 460 = GTX 460?

there are 3 variant for GTX460. GTX460 1GB, GTX460 SE 1GB and GTX460 768MB. for the 1GB version the one with SE suffix are slower than the normal one(some poeple called it as Slow Edition   ). in fact the SE version is slightly slower than GTX460 768MB. the SE edition only have 288SP compared the other two which have 336SP. for your second question actually the difference in RAM alone wont make the very same card have different performance. but normally the extra RAM will help you when you play with bigger resolution or if you want to crank up the setting such as AA and AF since you have extra memory. but in case of GTX460 1GB (the normal one) and GTX460 768MB they have different count of ROP as well. the 1GB model have 32 ROP and the 768MB have 24. that's why GTX460 1GB are faster than GTX460 768MB

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