Good evening,

I have researching for a few months now about looking into either a Radeon 6970 or using 2 6870 in Crossfire. I currently have a MSI Twin Froz 2 6870 already OC 930mhz. I have in mind of getting another MSI twin froz 3 already OC to 930Mhz. My questions and concerns are the following.

1. I currently have a 750 watt PSU will I need upgrade to a 850 watt for stability?
2. Will these two cards enable better performance to run games like RAGE, CRYSIS, SKYRIM on possibly max settings?
3. My mother board has 2 PCI EXPRESS SLOTS for Crossfire but downgrades to 8x8x config instead of 16x16x will the performance suffer or should I get a 6970 high end card?

Any Further advise would be great please let me know whenever possible.

Thank you,