» Mon May 14, 2012 4:18 pm
A likely problem, at least for the OP, is low CPU clock speed. This game doesn't care if you have more than two cores, it only cares what speeds you're clocking. It cares a lot about the speeds you're clocking.
http://www.tomshardware.com/reviews/skyrim-performance-benchmark,3074-9.html
The link shows that high clock speeds are much more important than the number of cores beyond two. You can see in the second graph that increasing the number of cores beyond two doesn't actually affect performance.
Huge oversight by Bethesda, not including support for more than two cores. This game is severely CPU bottle-necked, and we're pretty much SOL until someone comes up with a solution to this, be it the modding community or Bethesda themselves.