I'm looking to build a gaming PC.

I've picked out a Gigabyte Motherboard,
http://www.newegg.com/Product/Produc...82E16813128423

with 6.0 GB/S Sata, and USB 3.0

Probably get a low-end Core i7

question is what would be the sweet spot for a video card.

Biggest requirement, is that it has to play STO at 1920*1200 on my Dell 27" display. (at 30-60 FPS)
All the eye candy, I can take it or leave it. if I can have all the detail sliders at max, and 2x AA, for $150 I'd snap it up in a heartbeat.

My current computer is a MacBook Pro with 4gb of dual channel ram, will 3GB of triple channel be enough on the new machine, or do I really need to spring for 6?

thanks for your help all...