I've got an ubuntu 11.04 install with ati 11.3 drivers and a 5970 and 4830.

aticonfig shows all cards and the I can interact with all cards.

However, when running any of the miners (poclbm, phoenix, cgminer) they just hang after pressing enter. No error is thrown. Sometimes they hang immediately, sometimes it'll connect to my localhost bitcoind and then hang.

I'm having trouble diagnosing the problem. I've tested the various components, ran memtest for days, ran cpuburn, etc.

Any ideas what could be wrong?

Thanks much!