Performance lower than expectations, P-7811FX

That does not sound right to me either, I have the 6860FX (8800gts) and I am cranking way higher than those numbers. A couple of differences though that does make a difference is that you have the high res WUXGA screen opposed to my whimpy 1440x900. BUT TF2 definitely should be well over 60FPS. After your format and I assume you are running Vista, you need to make sure you re-installed some extra drivers such as intel inf updates (chipset) as well as any speedstep type of drivers if any. Also make sure if your system has dual drives that you did any drivers pertaining to the Intel application acceleration for the serial interface chipset.

Sometimes after doing a fresh OS install these items may be overlooked but in my experience with laptops you should ensure to do them.

I always do the stock drivers first before using any modded ones.

Make sure the power settings are set correctly while plugged into the wall outlets and that your system somehow is not running on some balanced or low power profile in the bios, as well in the nVidia drivers settings, and for the power profile in windows itself. It should be set to High performance when on AC power. Or else you may have your cpu and gpu running in power saving mode not performance.

Also check the games video settings for vsync being on (although I am sure if it was a vsync issue you would at least get 60fps max but not more.)

If you already thought of this, then I am not sure what else it could be. Other than some driver issue.