intel i7 4940mx available speeds are wrong

[roger lawhorn]

My laptop is a msi gt70-2pe.

I upgraded from an i7 4810mq to a i7 4940mx.
This cpu is 3.1ghz with turbo being 3.8ghz.

The top speed is listed as 3.3ghz turbo.

I uninstalled the app and reinstalled.
I now am set to 3.3ghz by default with 3.3ghz (turbo) not selectable even though it is on the menu.
I do use intel_pstate=disable on my command line.
In my bios I use default values and intel speedstep is turned on.

Any ideas?

Can someone explain if pstate is preferable to no pstate and why?