5830 & 5870 - first is like 100-110mhash/sec, other is 230?

[pervert]

There is no difference in config between the two cards, i use the latest catalyst with no SDK. I am reading that the sdk and driver versions will be affecting the performance, but from the get go i am sure the 5830 should be fairly close (or atleast drastically closer than it currently is) to the 5870. I have crossfire enabled for gaming, but i still have to select each gpu individually in guiminer. I think there is obviously another problem occurring here that needs to be rectified before i can tweak the performance of both cards. I searched for a while on the forums but i dont see this particular problem. Could it be power related? Its only a 500watt ps, and maybe the 12v rail the first card is pulling from is weak?

Any insight would be wonderful,
perv

[Jdumond]

do the cards start out mining significantly higher and then drop?


regardless of that,

1. Disable crossfire
2. Check temperatures-If your card is running too hot it will not perform.
3. get SDK 2.1


EDIT* if it was power related it would most likely overload and shut down, as the case was for my first two rigs.

[pervert]

took machine apart, changed the 12v connectors to spread from different rails, blew it out (though there wasnt much dust) - works fine now. might have just been heat, but it was under 65c when it was doing 110mhash. both are over 200 now...time to try and tweak