Unusually slow graphics

Recently I decided to get the orange box from steam after taking a long hiatus from gaming in general. After installing TF2 I hopped on a server with a friend and noticed that I was getting horrible framerates. I thought this was unusual because about a year before when I played half-life 2 and counter-strike source I was getting much higher framerates. I tried reinstalling drivers but that did nothing. My computer had been getting pretty bogged down considering I hadn't reformated in over 2 years so I decided to reinstall windows and format my drives. After a complete reinstallation I tried TF2 again and was still seeing the same problem. It wasn't until last night that I was completely convinced something was horibly wrong when I played Counter-Strike 1.6 with some friends and noticed that I was peeking at around 80fps and would experience about 50-60 when in graphically demanding battles (I did set my fps_max to 100 for those who know about that). In the past I would always get a constant 99.9-100fps in this game, it's praticaly ancient(but still the best ). Any suggestions?

Graphics card: GeForce 6800 GT 256mb
Driver: nv4_disp.dll version: 6.14.0011.6375

Alright, I rolled back the drivers and got some great results with CS 1.6. My TF2 is still a little slow but that just might be what I can expect from my card.?

Also I checked the heating, it seems to be fine.

Anything else that could cause it?

Could you run CPUZ and check what the Link Width of your PCI-E is running at and let us know?