What graphics card is suitable for my system?

Hello, I've been agonizing over which bang for your buck performance graphics card I should buy with my current build. I've been looking at the Geforce 600 series from the 650, 650 Ti, 660, 660 Ti, overclocked, non-overclocked, 1 GB, 2 GB. You name it. I've recently scanned the AMD side of things with the 7850, 7870, 7950 (overclocked and non-overclocked) respectively.

I want to be able to play intensive games on my 1600x900 resolution (I realize it's not truly "HD"). I also want to be able to fit the graphics card in my power supply requirement of 500 W maximum. Noise and temperatures heavily weigh in as well. Coil whine is a big no-no, and any cooling solutions that utilize a relatively silent way of doing things would be greatly appreciated. I am a bit obsessive about keeping my graphics card (optimally) below 70 C.

I don't plan on manually overclocking, so that's why I was looking into factory overclocked hardware.

My price range is from $200 to $300 (with a ~$15 margin).

Here is my setup so far:
PCPartPicker part list: http://pcpartpicker.com/p/CCmi

CPU: Intel Core i5-3570K 3.4GHz Quad-Core Processor ($189.99 @ Microcenter)
Motherboard: Intel DH77EB Micro ATX LGA1155 Motherboard ($95.24 @ Amazon)
Memory: Corsair Vengeance LP 8GB (1 x 8GB) DDR3-1600 Memory ($39.99 @ Newegg)
Storage: Toshiba 1TB 3.5" 7200RPM Internal Hard Drive ($69.98 @ Outlet PC)
Case: Corsair 300R ATX Mid Tower Case ($59.99 @ Microcenter)
Power Supply: Thermaltake TR2 500W ATX12V Power Supply ($32.99 @ Microcenter)
Optical Drive: LG GH24NS72 DVD/CD Writer ($18.98 @ Outlet PC)
Case Fan: Rosewill RFX-120 87.5 CFM 120mm Fan ($4.99 @ Newegg)
Case Fan: Rosewill RFX-120 87.5 CFM 120mm Fan ($4.99 @ Newegg)
Case Fan: Rosewill RFX-120 87.5 CFM 120mm Fan ($4.99 @ Newegg)
Case Fan: Rosewill RFX-120 87.5 CFM 120mm Fan ($4.99 @ Newegg)
Monitor: HP W2072a (A3M50AA#ABA) 60Hz 20.0" Monitor ($109.99 @ Amazon)
Keyboard: Logitech MK200 Wired Slim Keyboard w/Optical Mouse ($22.41 @ eCost)
Total: $659.52