cjrgreen: What do you get if you do knock the resolution down to 1280x720?

If that doesn't improve your 25 fps to better than 30 fps, then I'd suspect you are CPU-bound.

This game spawns a lot of threads, which may cause your Q920 to fail to go into turbo boost. I haven't seen this suggestion for TW2 yet, but it's been successful for some others:

With TW2 running, go into Task Manager, find the executable (witcher2.exe), right-click and choose "Set Affinity...", and deselect half of the cores. (I think you will see 8 cores; deselect all but CPUs 0, 1, 2, and 3.)