Thank you, IAmTheRad. I had a sneaking suspicion it was optimus. I had been doing exactly what you said and I'll continue to do so. The nvidia card only runs TS3 at a maximum of about 70 fps anyway but I didn't want to take any chances.

I'm getting a strange error when trying to use 3booter and FPS limiter to start TS3 on my laptop. The dos prompt will show up as usual, then I get the error message "The application was unable to start correctly (0xc0000005). Click OK to end the application." I have a desktop that runs FPS limiter just fine, so what's going on with my lappy?

Laptop specs:
ASUS U31SD-XA1
Windows 7 Home Premium 64 bit
Core i3 2.1ghz
4GB RAM
nvidia geforce gt520M 1GB + Intel integrated (optimus)

Desktop specs:
Windows 7 Professional 64 bit
AMD Phenom II x4 Black 3.2ghz
4GB RAM
nvidia geforce 8600gt