Well, in that case you should just go for a GTX 580, I only know the UK prices, but I'd be very surprised if it wasn't in your price range. If you prefer AMD you could go for a 6970; my personal preference is the 580, but on average they are quite level, superseding one another in different games. If you are interested in 3D Nvidia is definitely the way to go; furthermore you have PhysX with Nvidia, sadly it's not used as much as I would like, but it still makes a big difference to games that support it.
If you are looking for multiple monitor setups AMD is the way to go.
Looking at your general specs, your Corsair 750W PSU can be taken down to something like a 650TX without causing any issues. I'd also get a slightly better motherboard (money saved in one place, invested in another!). Furthermore, for the sandybridge platform, you only need a bare minimal CPU cooler. Unless you're heavily focussed on OC'ing (4.7Ghz+ and such), a cheaper heatsink such as the CM Hyper 212+ will work fine. I'm not sure what ambient temperatures you experience over the summer, but when I was testing the 212+ with sandybridge I found that an ambient of 35°C with a 4.5Ghz OC on Prime 95 and the CPU started to run at 70°C.
You could also invest in an SSD if you're interested, that could provide a viable improvement rather than a motherboard upgrade, that is if you're interested in changing any aspects of your build .
580 sounds perfect, I was leaning torwards it, as I too prefer nvidia.
I don't mind changing anything else, 650 watt sounds good I was looking at ssd's but I was hopeful they would get cheaper in the bear future.
As to a better motherboard what would you suggest?
Thankyou for the reply
a better motherboard would be the asus maximus or the p8p67 pro or deluxe
as for a video card, a gtx 580 is overkill for your resolution, a 570 or even 560 ti would be plenty to handle your resolution. if you dont plan on upgrading to a 1080p monitor, buy a 570 or 560 ti and save the money
Ahh, I hadn't read your screen resolution; r3xx3r does make a good point, although I do not entirely agree with it. The 570 will offer you complete current-gen performance at the resolution you specify; however if you choose to upgrade your display at any point it will falter, the other question is how long you want your computer to last, needless to say the GTX 580 will offer high-end performance at a given resolution for a longer period of time, but strictly speaking it isn't required. I think saying the 580 is 'overkill' is taking it a bit too far, if you max metro2033 at the specified resolution you wont get a nice and smooth 60fps, and in my eyes something only becomes overkill when there are no situations in which it is noticeably advantageous over lower-end hardware.
Fundamentally if you're saving the money on the graphics card now, you'll have to buy a new one sooner - if you're the kind of person who regularly saves money for future hardware, it probably isn't worth getting the 580 now that I've seen your resolution if you have no monitor upgrade plans. If you're the type who has this money right now, and if it doesn't go on a computer it'll be spent elsewhere, I would get the best you can currently afford, and run it for as long as possible.
In terms of motherboard the Asus Maximus is on the expensive side of things, but changing to a P8P67 Pro/Deluxe would be a welcome improvement, I suggest you have a look at the specifications and decide what features you find appealing .
After reading the above posts I have a couple of points to make. These are just my opinions though.
Don't go for 650W PSU stick with the 750. With that rig and possibly a 580 installed it's gonna need plenty of juice and you don't want to work your PSU hard if you want it to last. Also you'll get more life out of a 580 at 1680x1050 so I don't thin it's over kill. I have an HD5970 at 1680x1050 although I use another display when playing FSX but this was a deliberate decision to retain good frame rates for longer. I'd seriously consider a 6970 though but again just my opinion.
I have decided to go with the p8p67 pro or deluxe and a 580 to ensure a little more longevity out of my system, I do plan to upgrade my monitor later this year. To kkkk1, i think i will keep the 750 watt psu.
@ Wampbit, i think i will go for the 212 cooler.
Thank you all for your very fast and helpful replies