Help with my build please?

Right now I'm looking to get the Gigabyte GA-990FXA-UD3 mother board, and this AMD CPU . And I want the XFX AMD Radeon HD7870 2GB DDR5 2DVI/HDMI/2x Mini Display Port PCI-Express Video Card. The thing is, I'm not sure if the video cerd will work with this mother board because the card is DDR5, and the board is DDR3?

If this card wont work with this board, and only if, do you have any suggestions for a differant Graphics card? I have a budget of around $250 for this alone.

The motherboard uses DDR3 RAM, this is different from graphics memory.

Your motherboard takes the card fine so dont worry about that, in fact your motherboard can crossfire 7870's if you wanted too.

I would reaaaally reccomended you get a fx 6--- or fx 8--- instead of the fx 4170 though, it just doesnt have enough power in my opinion and its not a true quad core.

Also, you will have to look at DDR3 RAM make sure you dont try and shove some old DDR2 in there.

All your parts are compatible. The DDR3 is for you RAM and the DDR5 is whats inside your Graphics card. Your graphics card will fit in you motherboard through a PCI express slot. I would recommend for your build that you use a "Piledriver" AMD FX 4300 instead of the "Bulldozer" AMD FX 4170, because of how much of a better performance you get from it for about the same price.

Also, the graphics card is pretty much the best price/performance you can get at the moment and is a great card.

+1 for the Piledrive CPU's over Bulldozer anyday

Thanks for the help! So is this more like what you guys are thinking of for a CPU (I decided to go 6-8 core) ? Also, what cooling system would you suggest for this? I imagine an 8 core will get much more hot. Anything but water cooling, and preferibly not too much money. It will also be able to fit in a Corsair Vengeance case. And last of all, I'm getting Mushkin Redline DDR3 Frostbyte RAM, so I should be set there. Thanks again soooooo much!

Well if you want good air cooling, the Cooler Master Hyper 212 evo is a good way to go.