Just an observation on Windows 8 that I wanted to share which may also help others using Windows Vista and 7.
Recently, I was seeing some graphical glitches occur under Windows 8 as well as CPU usage getting stuck at 25% for unusually long periods of time on my quad-core i7 desktop. This meant that one core was being consumed persistently for no apparent reason. Obviously, this isn’t a good thing particularly with power conservation coming more into focus these days. The offending process was noted as COM Surrogate which maps to dllhost.exe in Windows.
In order to unstick the process I would reboot my computer which would temporarily resolve the problem but it would eventually come back.
I thought that perhaps the video drivers might be causing a problem so I rolled back from the official nVidia drivers to the standard drivers included with Windows 8 and restarted the system. Having done that a couple of days ago things have been working fine ever since with no further video glitches or processes chewing up the CPU for no reason.