Get a single GTX 670. It can steer 4 monitors and a second card is not used by PR. If you install only a single card, it will run at PCIe-16x, but with 2 cards, both will run at PCIe-8x and one will be idle.
Like Harm said plus get a Cooler Master 212 EVO cpu cooler and overclock at least 15% if not more. Your 2700k cpu cooled properly is extremely easy (and safe) to overclock and you will definitely see measurable improvement in your renders.
Thanks for the advice to overclock my cpu I'll be sure to do that once I've got the graphics card. About the Cooler Master 212 EVO cpu cooler, I've already got this Titan Super Quiet 22dBA CPU Cooler over my processor do you think this would do the job. If not I can always purchace one since the Hyper 212 Evo isn't that expensive.
Thanks for both of your help...
The Titan looks fine.
>often find it's my graphics that freeze up
For video editing, you need to scale your pictures before importing into Premiere Pro
Photo Scaling for Video http://forums.adobe.com/thread/450798
-Too Large May = Crash http://forums.adobe.com/thread/879967
-And another crash report http://forums.adobe.com/thread/973935