There is no noticable difference in performance... For the 1% still on 32-bit systems, I'd recommend to upgrade as soon as possible, as not all those systems will handle the minor memory increase.
Whether the "1%" is literally true or not,
this ... start planning your move to 64Windows ASAP. I'm not sure how much time you do have, but I'd be surprised if it were as much as a year.
How much RAM do we need to run EU4 now?
The published spec stays at 2gb I believe. But in practical terms I agree with Johan; a 64bit OS and 4gb of memory is the operational reality now. 4gb under 32bit Windows is still a problem, because 32bit Windows limits all apps together to only 2gb of memory anyway, even if you have 4gb installed.
Good god. Is there a limit to optimization? I want to see 5000 provinces with the same gamespeed eventually.
There sure is, and in all honesty I wouldn't rely on optimization to solve this problem forever. CK2 hit the limit about 2 years after release with a major map size increase; here we are just over a year after EU4 release with a large increase in province numbers. I would take this as a straw in the wind and start planning your move to 64bit Windows ASAP.
Is the CPU that important? Gfx card RAM helps more after loading up the game doesnt it ?
They are all important in various ways. But video memory is least of all
once you have enough; the benefit between say 1gb and 2gb, or 2gb and 4gb, is minimal. It's the GPU's processing power we use.
In PDX games CPU/RAM are very important, you only really need an integrated GPU.
Not true at all, I'm afraid - we use the GPU for various classes of calculation at which it is better than a CPU. I'd go as far as to say the GPU's processing power is the single most important hardware factor, once you have adequate system and video memory.
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