With my 335m I use 295.73
Note that some drivers just fail with my m11x because it has the switchable GPU. Some games (Like FFXI) will even use the intel chip when they load even though I had it set in the BIOS to only use my 335m. This will only happen with some drivers (285.62 for example)

Iv had luck in FFXI with...
263.08 (The one from Dell)
266.58
295.73 (Current driver I use cause it works for XI and XIV)