new kde on f13 is very noisy!

[Chris Rouch]

Over the weekend yum pulled in the newest version of kde for f13
(4.5.2 I think). Since I rebooted and logged in my laptop seems to
have the fan going most of the time. Gkrellm shows both CPUs are doing
something, and top confirms that kwin and plasma desktop are each
using between 10% and 30% CPU. For comparison on my f12 desktop at
work they use between 2 and 5% cpu.  I don't know what the used before
the upgrade, but I do know the fan was usually off except when the
machine was loaded.

This happens with only one window (firefox), and that only having a
couple of tabs open.

Is this something I can change? If so, where do I need to look?

Thanks,

Chris