I'm running Ubuntu w/ x2 5830. First card is performing well but whenever I try to get any stat on the second card I get something like this:
Adapter 0 - ATI Radeon HD 5800 Series
New Core Peak : 900
New Memory Peak : 1000
ERROR - Set clocks failed for Adapter 1 - ATI Radeon HD 5800 Series
Please check that input values were valid
EDIT: More general case
No device specified or device not found, use DEVICE=ID to specify one of the following
- AMD Sempron(tm) 145 Processor  Cypress
1) Are you using any PCI express risers? If you are, they must be defective (my were).
2) Make to reconfigure xorg with
if a new card is installed.