I've had problems with svchost.exe before, but now I am getting my RAM stolen by svchstx.exe. Its taking anywhere from 50% - 95%.
I personally have never seen svchstx.exe at all before this, but if anyone could tell me what it controls or what it does, I may be able to fix it. :S
The description for svchstx.exe say's it's from Microsoft and has over 450,000K local memory being used.