Switch that HDD to a Samsung Spinpoint F3 500GB. Its faster, quieter, and only $54.99
I would at the very least upgrade to the HD5770. Its a little more, but HD5750 is not worth the money. The powercolor HD5770 on newegg is $149.99.
The motherboards are pretty similar, the 880 uses the new northbridge, but thats not as necessary with a discrete GPU. I would say either the 790XTA or 880GA, maybe wichever one is cheaper.
Check out frostytech.com for the top rated HSF. That freezer pro is decent, but old, there are a lot better options these days.