Guild War problem on geforce 8600m GT

Hi, I've been having this problem recently for 2 weeks or so.
Here's screen shot


The symton of problem is game freezes for 2 seconds and ingame graphic becomes messes up as screen shot. I can fix the graphic problem by restarting laptop again or minimize windows and maximize again to correct the problem. But going in and out of zone will take few seconds longer to load when this problem occur and not rebooting laptop.

I've monitored the temperature and GPU temperature is within 87 degree celcius (I don't overclock GPU). And temperature has been this since I got this laptop day one and was all normal.
Several methods done in past including game re-install, trying several graphic card driver, different direct x 9.0c runtime, reformatting windows system.

This problem only happens on Guild War and not on other game.

My comp spec as of my signature. Any help is appreciated

 

Have you tried asking on Guild Wars forum boards?

 

Nvidia GPUs have been known to cause certain issues with Guild Wars sometimes.

If you have the Nvidia control panel, set the GPU to "high quality" rather than "high performance" or any other mode. That should resolve the texturing problem according to Anet.

 

have you used texmod with guild wars? i used to get problems like that after modding the interface and such

 

Is there official guildwar forum? I tried high quality and it doesn't solve the problem sadly...
I don't use any 3rd party program.

This problem doesn't happen before but only recently. So I'm really puzzeled.