XFX 9800GTX+ Review
 

Since this card higher speeds from the start I had to wonder how much was left in the tank. As it turns out the tank had some gas left. I kept bumping it up and up until I hit the wall on the core and then the same with the memory. Then I had to find the best combination of the three clock speeds. Once I reached about 840-850 MHz on the core I was getting crashes, so I used RivaTuner to unlink and back down the shader cores a touch to move the bar a little higher. This yielded an increase on the GPU core of 123MHz and a final speed of 863MHz. The shader core clock increased by 235MHz and 150Mhz on the memory. All pretty substantial increases on air cooling. Speaking of cooling the stock cooler does a great job cooling this smaller core.

http://www.overclockersclub.com/reviews/xfx_9800gtx_/