Help, I found my Skulltrail

Okay.. Was going through my storage unit today, and saw a crate I forgot about, I cracked it open, and Inside it was a Box labeled "Dead Board, Bad Bios"

Well I opened it up to find my Skulltrail board, Which i thought Angel ran off with. Pulled out 2 Harpertown X5450's, 2 Stock 775 Coolers for the P4 560's, 8GB(2 sticks) of FB Kingston ram(KTM5780), and dropped a GTX 260 216core edition in it. Has dual 750 watt PSU's atm and is in a AZZA Genesis 9K case. What do ya know, It powered up right.

So here comes the questions XD

I won't have time till after Christmas for it,but Who wants to help me OC this ***** and can anyone tell me if this GPU bottlenecks the system or not. I've been told that it only works fully with certain GPU's but i thought like everything after the 9 Series worked properly. Idk remember much on this board, so I'd love some experts XD

How would a GPU hold back CPUs? That doesn't make any sense to me. What are you trying to do with it in the first place?

It's multi purpose. gaming, Video Editing, Audio editing. Also I've been told before that certian GPU's will cause the system to use 1 bus instead of all 8.... It made no sense to me either.