I'm sorry I don't know a great deal about motherboards, but i had a look at the one you suggested in your OP and it looks like a great board with plenty of room to upgrade. Its got the Crossfire support which is great when/if you want to upgrade, tho if you are going to do that a bigger PSU will be needed.FieryTrainwreck said:Do you have a specific mobo recommendation? That's the most confusing bit; seems like they've got about 20 boards with a handful of minute differences for roughly the same price.TheComedown said:For your price range and what you want to do the 550w you recommended should do fine unless you plan on upgrading to crossfire. Stick with the amd gear here, you'll keep the price down and you'll find that almost all of the ati cards have a much better power consumption then the nVidia equivalents with little to no performance loss.
As for the rig you specified it looks good. My only recommendation would be to get a better graphics card, RhombusHatesYou suggested the 5770 and for what you wish to do its probably the best option to keep down costs but still have the power. I have the HD5770 OC edition and it runs most modern games maxed out at 1680*1050
One last thing I would suggest tho is a different case. I don't know your price range but I always recommend the Xigmatek Midgard over the 300 as its got a fair bit more room, solid drive bay clips (and more bays including an external 5.25" to 3.5" adapter) and its only a fraction more expensive then the 300.