I believe this is the computer that
@BrandonW77 recently bought and I believe it was in the upper end of your price range, but he'd have to confirm that, I don't remember off the top of my head.
http://www.newegg.com/Product/Produ...9375X1015946Xe028c28c64c75be11e442bac9e435f59
At around $800 you're kind of in the price range where you'll get a good i5 processor that's more than up to the task, but you get a midrange card with it. For that extra $100-150 you get the 970 or equivalent card and with everything else the same you double the performance of your system. Do you need double the performance most of the time to run a game at 1080p/60fps? Probably not. When might you need it? All settings maxed out and/or massive grids offline with full weather, day/night, full damage etc. What happens if you want to run those same settings with a mid-range card? You might get less than 60fps when the system is stressed out, like at race starts, when the weather kicks in with lots of cars on screen etc.
The 960 is a good mid-range card that will run the game with an i5 quite well and if you notice issues offline in the above conditions you can always turn down the eye candy to maintain the frame rates if necessary. So really it's a question of spending that extra $150-200 for the extra insurance and some future proofing or conserving the cash and working around the shortcomings, if any, of the weaker GPU. If you want to simply match the mid-range console settings you should be fine as well, the GPU really only gets stressed when you are far beyond what you are going to see on console, like trying to race with GT5 Photomode quality cars vs. the slimmed down console display of 60K polygons.
A quick search found this:
http://www.newegg.com/Product/Product.aspx?Item=N82E16883230007
Also, use this for reference,
GPU Benchmarks It's pretty much a linear scale, in that a 9000 benchmark will give you double the performance of a 4500 benchmark, all else the same. You can do a search at the top right if you don't find a car. The
GTX 745 for example benchmarks at 2160, whereas the
GTX960 benchmarks at 5994. The system above is $799 and would be far, far better for gaming than any of the systems with lesser cards in the same price range.