a) How do i compare results between slow and fast cards then? How compareable are results achieved with different versions of futuremark?
Result between different 3DMark versions are not comparable. And comparing GF4 and GF6 is difficult - usually you can compare just fine cards that are like generation 6/7 5/6 etc don't have too big tech gap.
3DMark usually focuses new (DX) tech like new shader versions and are meant for testing those card generations, like latest Mark was for DX9(SM3) cards. So it should be mainly used for comparing DX9(SM3) cards because SM2 cards can't run all the tests - thus results are "wrong".
You CAN however use whatnot cards and compare them using whatnot 3DMark if they both can run the same set of tests.
IMO 3DMark is especially good for deciding what new card should you get and comparing those. Older cards are obviously slower so it does not make sense to compare new cards to old ones?
b) It's kind of boring doing a years old test on a slower card isn't it?! Should be obvious for people who come from the demo scene...
? Didn't quite get what was the question?
c) Also how are features of newly released low range gpus tested where the featureset is richer than what could be tested in older versions of futuremark?
Well it's all about what SM level etc they have and use approriate 3DMark for testing. They will get bad scores but in their range the result are comparable.
d) If i have a slow and a fast gpu doesn't this also mean that i'll have to buy more than one benchmark?
No - 3DMark is free you know! :) Seriously, like I said it's all about the tech level of your GPUs. Different SMs (Shader Models) for example require different tools (3DMarks) to test them properly.
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