I was using 306.xx driver with my eGPU setup (Dell e5520 - PE4H 2.4 - gtx580) and I was able to enable optimus by simply press F8 when win7 loading and plug in eGPU then continue booting.
lately I got another laptop (Dell e4300) so I tried the same eGPU hardware on it but withe the latest (310.xx) driver. I cannot enable optimus with all 3 options: a) boot laptop with eGPU connected. plug in eGPU after bios check but before win7 loads. c) plug in eGPU after win7 loaded. all three options work in that I can use a monitor connected on eGPU to utilize nvidia card but internal screen can only use integrated gpu.
then I change to the older 306.xx driver, and now I get optimus (internal screen can utilize nvidia gpu and can choose which gpu in nvidia driver panel).
has anyone tried the latest driver and noticed the same issue?