For the past 2 cards I've used AMD, so I think that I am going to use nVidia for my next gaming solution. With SLi does it have to be the exact same card for SLi to work? And how does a physx card work, does it need a separates card for it? I know that no one can guess performance figures but I want my next computer to be able to run Dirt 3 and Bf3 at max settings @ 2560x1600 with no overclocking. Will upgrading to a GTX590 do the trick or do I need more upgrading? I would also like it to be a "green" saver in both cash and wattage. I would recycle what I could from my current pc. would sandy bridge work, Should I wait till PCi 3.0 comes? How much ram? Should I upgrade to a new sound card, are they worth it, does it give me an edge in Shooters? This is nothing that I'm rushing to build, I'm just planing my budget and parts.
for sli you need to have 2 cards of the same model, but you can mix and match brands. for example you could do an evga gtx 560 oc and an msi gtx560 frozer without issue, however if the clocks don't match it will drop one to the lower of the 2. if you have 2 cards you can designate one as a physx card instead of using sli, or you can do 3 cards and do sli + physx. when doing a 3 card set up you can mix and match stuff from different series, so for example you could sli 2 gtx560 and use a 200 series card as a dedicated physx. but there is no need to have a dedicated card for physx, it will work fine with a single gpu. in regards to the resolution, i'll not comment as i have nothing that is in that range so i'll leave it alone. as far as green components, i am not aware of any in the high performance category currently, either its green or high performance, not both. if you're not in a hurry i might wait until ivybridge and see what that brings. in regards to ram i'd say 8gb is a good balance, unless you are only using 32 bit software, then theres no reason to go beyond 4gb. i'm not an audio guru, but if you have the budget for a good sound card theres really not much reason not to get one. i'm not so sure if it will really give you an edge or not unless you take the time to do a proper speaker set up to give you accurate positional audio in say a 5.1 set up in you room.
ivybrige will have another die shrink to 22nm, and is rumored to have improved on chip graphics, pci-e 3.0 and native usb 3. intel is also claiming a 20% performance increase over sandy bridge. there will be new chipsets for it which may end up being better than the current as well. though you may very well be waiting until this time next year before it arrives.
