Welcome to bleepingcomputer!
It looks pretty good, except you should get a different graphics card. That one is really old, and they stopped making them a long time ago. It is very overpriced. For around the same price you can get an ATI 4850 which dominates it http://www.newegg.com/Product/ProductList....=Radeon+HD+4850
. I'd recommend the sapphire or the HIS one. It would be better to get an ATI graphics card with that motherboard anyway because you can do crossfire (two ATI cards), but that motherboard won't work with SLI (two Nvidia graphics cards). The only other problem I see is that the second pci express slot only runs at 4X bandwidth, and this will slow down a second graphics card a bit. If you really want to go Nvidia though, I'd recommend a 9800GTx or the 9800GTX+. If you don't want to spend around $200 though, you should get an 8800GT. An 8800GT is better than the 8800GTS 640mb version.
I don't know much about liquid cooling, but you might want to get a full size ATX case to fit it all. On top of that, I don't know how much power a liquid cooling set up uses, but without it a 600 watt power supply would be more than enough to run your system.
Lastly, you didn't add an optical drive (A DVD/CD drive), or an OS. I assume you probably have those already, but just wanted to make sure you didn't forget anything!
"I think there is a world market for maybe five computers." - Thomas Watson, Chairman of IBM, 1943