I’ve already wrote about setting processor affinity for a certain task or process using taskset command using Linux scheduler utilities. Now Linux gets completely fair scheduler (CFS):
The new CPU scheduler includes a pluggable framework that completely replaces Molnar's earlier O(1) scheduler, and is described to 'model an "ideal, precise multi-tasking CPU" on real hardware. 80% of CFS's design can be summed up in a single sentence: CFS basically models an 'ideal, precise multi-tasking CPU' on real hardware.
Please note that scheduler matters more for Linux servers and not for your desktop system. However it is belived that CFS may help improve the situation for poorly written X driver.