We have got our hands on what are claimed the final clock speeds of the GeForce 9800 GX2 and if these numbers are indeed correct, then this card might not be as fast as expected. The GeForce 9800 GX2 have been dismantled some time ago, but NVIDIA still holds the card's detailed specifications tight. But finally we now know their little secret. The core clock is similar to the GeForce 8800 GT, but the memory clock has been raised up to 2000MHz. Also, our source mentioned the card supports OpenGL 2.1 technology. Therefore, the performance is estimated to be just slightly higher than two GeForce 8800 GT cards in SLI configuration. However, no card makers have received working cards. - FudZilla

NVIDIA GeForce 9800 GX2 Final Clock Speeds Ready

So to make it a bit more clear for those who haven't been able to deduct all the information, the GPU's will be clocked at 600MHz, that's 50MHz slower than the GeForce 8800 GTS or the same as the GeForce 8800 GT. The shaders will apparently be clocked at 1500MHz, again slower than the GTS which has its shaders clocked to 1625MHz. The memory clock is somewhat higher at 2GHz effectivley for the GDDR3 memory chips, but this is a mere 60MHz faster than a stock clocked GeForce 8800 GTS and is unlikely to make a huge difference. Not exactly spectacular numbers, but the cards are expected to run quite hot as it is.