m1730 SLI flickering and horizontal screen tearing

Hi, on my Dell XPS m1730 8700 GT SLI laptop...in single-gpu performance mode SLI setting, TF2 has the horizontal ripping/texture glitches and flickering (whole screen sometimes) problem all the time. I can make it happen when I look into the sky...e.g. sky in the Dustbowl map...


I've tried many things from scouring forums and that...

If I disable SLI, no problems
If I use AFR Mode 2, no problems...but lower performance

changing to higher/lower resolutions, still issues...
vsync on, triple buffering, threaded optimization, anisotropic filtering 2x all on, still issues...
in fact triple buffering makes all the shadows in my Teamfortress 2 flicker/blink all the time
fps capping in game to the 60hz (lcd refresh rate), still issues

169.28, 167.55, 167.27 drivers all have issues
156.55 seems ok...but real poor TF2 and Hellgate London performance

Would love to use 167.55, seems to give me the most improvement, but...anyone know why Single-GPU Mode SLI is causing these issues?

Anyone else have these problems?

Hope someone can help!
Thanks in advance!

 

Turn off vsync. I'm not sure if TF2 can be played in DX10, but if you're in DX10 try running it in DX9

 

thanks, yeah I've turned off vsync and the problem still occurs...

tf2 isn't a dx10 game - i'm running on dx9/9.1

anything more to try anyone?

thanks!