Lenovo T400 Graphics Switching Not Working

[Lavarin]

So, after a long day at work, decided to fire up a shooter on my T400, switching it to dedicated graphics. Unfortunately, after getting my ass handed to me, and switching back to integrated, the laptop now freezes. What could be wrong?

 

[MomoCC]

I believe you have to check your BIOS settings, which controls the fast switching of your Lenovo. Check the Display section of your settings.