ok thats sweet. while i have your attention, what is the cheapest psu (over 700watts) with 2 x 8pin connectors?
i really want the Matrix...
Probably better to just get a standard 7970 if you're having to get a new PSU as well.
http://www.overclockers.co.uk/showproduct.php?prodid=GX-273-AS&groupid=701&catid=56&subcat=938
Is a cracking deal IMO. You couldn't get 7950s for that price a while back.

Someone had to say it. 


. From memory I read somewhere that the 8+8 7970s actually functioned fine with a 6 to 8 converter anyway. I certainly wouldn't bother replacing an otherwise decent PSU for it when standard 7970s function fine with 6+8.