How to boost XP speed by by changing real time clock priority?

I read about this trick the other day over Internet.
Open Registry by going to START-RUN and typing REGEDIT.
Navigate to
[HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\PriorityControl].
If you see an entry by the name IRQ8Priority set it to a value "IRQ8Priority"=dword:00000001
if you don't then click on the right pane and add a new dword entry with given name.
IRQ8 is typically reserved for real time clock in most of the computers.
Make sure thats the case (by going to device manager -> system devices -> system COMS/realtime clock -> properties -> resources tab , if it is set to another number try adding an entry with that number N as IRQNPriority) . Generally realtime clock priority boosting helps most but you are free to try others as well.