MacBook Pro underclocking

I am sure everyone has heard about how the x1600 in the MacBook pro is underclocked to 310MHz (GPU) and 278MHz (RAM). Does anyone have any guesses on what effect this will have on performance? Has anyone tested it yet? They seem like pretty substantial underclocks to me.

Underclocked X1600 = games will run like crap.

Boot in XP and overclock it to regular levels using ATItool . You need your powercord and some sort of laptop cooling device to use an OC'd MBP for any length of time.

Overclocking tool.

http://macupdate.com/info.php/id/15849