Ok, had a one day delay as my Gb-E network adapter decided it wanted to go on strike.
mkk: It's not Vsync buffering, it's the actual render rate.
Here's a first look.
Settings: e8400 @ 3.2GHz
1080p
Animation: Low
AA: none
Environment: medium
LOD Distance: Low
Reflections: None
Textures: Medium
Render Sampling: Native
Shadows: Low
Shaders: Medium
Post-Processing: Low
Best texture filtering: off
Depth Blur: on
High-Res Character Textures: off
VSync: off
Unlimited Framerates: 205W, CPU utilization ~92%, GPU utilization ~94%
Framerate limited to 60fps: 185W, CPU 60%, GPU 50%
Framerate limited to 30fps: 155W, CPU 20-30%, GPU 28%
FRAPs logged the 2 minute runs from a keep, across a bridge, and attacked a couple of critters. With the frame limiter set to unlimited, I saw framerates from 43 to 111, eyeballed average is ~75. The 60fps limiter actually limited fps to 50 and the 30 to 25fps and they were both darn flat (which seems a little odd as I look at the frame times below).
I also logged frame times to get a feel for any wild/woolly outliers. Most of the unlimited frame times were in the 8-20ms range, the "60fps" limited were in the 15-25ms range, and the "30fps" limited were in the 30-50ms range. When I get some time, I'll upload the graphs.
In any case, the no-brainer is to set it to 60fps limiting and get 20W power savings. I'll also try the 30fps limiting and see if it's playable.

