^I agree. If there is wiggle room in your budget, check out the GTX750Ti or even the GTX750, either of which is stronger, and will also run Blizzard games (e.g. WoW) better.
Any of those cards will run on a quality 300W-350W PSU, so see if something like a Seasonic G360 or 380W Antec Earthwatts would save you some money.
The G3258 is intended for overclocking, and comes with a stock cooler that is suited to that purpose (it's the much heavier one, with the copper slug).
If your budget allows, get a 2x4GB RAM kit so you can run in the faster dual-channel mode.