I don't think it's the amount of purely the 1G memory factor, as older top-end cards only had 1-2G, recently tho top-end cards have 3-4g nowadays.Originally Posted by MaTiSpOrT
A lot of games are starting to become more and more GPU optimized (AMD mantle will come soon, but games need to be specialized for it however).
It's the massive differences in Memory Bandwith/Texture Fillrate/GFLOPS between video cards. (often you can see the differences in watts as well) that sets them apart.
System requirements can be misleading for AMD since 5000/6000/7000/8000/Rx200 series have a large range of cards, from budget to high end, while each time a new line of cards come out, it doesn't mean a higher number card makes it obsolete or is automaticly better as each production line gives like 10-16 cards.
My 5870 is only slightly below a R9 270, but the far newer card (november 2009 vs oct 2013) has higher clock speed and higher memory speeds, and supports directx 11.2 vs 11.0 cause it's 4 years further in tech. The r9 290 is much much better but far more expensive.
http://en.wikipedia.org/wiki/Radeon_HD_5000_Series
http://en.wikipedia.org/wiki/Radeon_HD_6000_Series
http://en.wikipedia.org/wiki/Radeon_HD_7000_Series
http://en.wikipedia.org/wiki/Radeon_HD_8000_Series
http://en.wikipedia.org/wiki/Radeon_Rx_200_Series
All of those specs in each series have clear differences especially in TDP (watts) / Texture fillrates / Memory Bandwith / GFLOPS (processing power)
I haven't used an Nvidia card for ages so I can't comment on those.
Keep in mind those are on-paper stats and not benchmarks, as each software handles differently.
Thank you so much for the interest!! At the moment I dont need a better card, so I can wait to buy a new one.
A pity, but at least i can play the Xbox version...