Overclocking
To find the maximum overclock of our card we used a combination of Rivatuner, ATITool and our benchmarking suite.
Just like all other GeForce 9 cards, the 9800 GTX also uses the "core clock derived from PCIE clock" feature as described
here.
The final overclocks of our card are 802 MHz Core (19 % overclock) and 1221 MHz Memory (11 % overclock). Those overclocks are amazing, but make me wonder why NVIDIA picked such low default clocks. Given the overall performance we saw, an extra 8% clock speed would certainly help the card's performance.
Temperatures
A temperature difference of 11°C between idle and load is extremely small. Even though the temperatures are nice they are unnecessarily low, it would be better to have the card run quieter with load temperatures of about 80°C.