I have found that tweaking with the refresh rate of the monitor will improve performance dramatically.
in XP...
In display properties, Click Advanced, then Adapter and press the button "List all modes". Find your resolution and Try one setting higher on hertz than the previous. If it the display loses synch wait a few seconds and XP will switch it back. Sometimes when you get a corrupted display you must go back down to 60 to correct it, then try again.
Some ppl will tell you that this might damage your monitor, but I have been playing with Refresh Rates in Linux 4 8 yrs and have never had a problem. But just the same -- You break it, it's your fault. *Grin*
I currently have my screen tweaked like this at home and have no problems.