Just a thought, have you tried GeForce Tweak Utility? it can be found here:
www.voodoofiles.com/5708
or have you installed this Warcraft III Patch? Blizzard has released the 1.01 update for Warcraft III, which comes in at a small 1.7mb. The patch includes 'various data and code updates necessary for play on Battle.net as well as some minor balance changes'.
It is found here:
http://ftp.blizzard.com/pub/war3/pat...r3Patch101.exe
good luck