Re: Stress Test Issues
ratings look reasonable.
Can you make sure each graphic card is on its own 12V rail? The rail (12V1, 12V2,...) should be printed either in the manual or optimally on the PCIe connector.
Otherwise, it could be either of the 9800GTX. If you do not encounter any problem outside of Furmark, I would just recommend to forget about it and just enjoy your setup.
As the universe is curved, there cannot be a straight answer...