Right click scratch, VM preferences, system configuration. Thread priority boost is checked, but the others aren't. Does reduce CPU usage actually reduce CPU usage?
Tip of the whatever: Don't post in threads older than 2 weeks unless your post will actually be useful.
It's the last day of 1.4! *cries* (quote from NeilWest, rest by me) by the time you read this it probably will be 2.0