I have a pair of Sapphire Radeon 5850's in my rig running Ubuntu 10.10. When I pull the cards with aticonfig, this is what I see;

* 0. 04:00.0 ATI Radeon HD 5800 Series
  1. 02:00.0 ATI Radeon HD 5800 Series


I am wonderig if anyone knows what the 04:00.0 and the 02:00.0 mean? I am guessing that is my firmware on the cards. Can anyone confirm or deny?

The reason I suspect this is that my second card seems to run a bit slower that the first. I see the same Hashes per second in Phoneix, but the number of accepted hashes on the second card always trails behind. Eventually it can get a hundred or so behind after a few hours (starting them at the same time).

Also has anyone upgraded firmware on their cards?

Thanks in advance.

Bus IDs actually, not exactly PCI IDs.