Crossfire issues

[SXRguyinMA]

I just got my rig back together, with 2 3870x2's in crossfire. Whenever I run Furmark, I can only get about halfway through a benchmark or about 10 seconds into a stability test and it freezes. The temps seem normal (each core running between 81-84ºC) I dont get an error messages when it reboots, it just boots back up normally. I've got the latest drivers installed and cant seem to figure it out. Anyone seen this before? :?

[wahaneebelly]

Now from what I understand with Crossfire, as long as they're from the same series, they're supposed by crossfirable and the higher card should match the lower card's clockspeed.I will be building a i7 920 rig very soon which will have two Asus 5850's in crossfire.