Does this mean its disabled and I cant enable it or enabled and I cant disable it? ANy idea why it is greyed out? ISSUE RESOLVED It appears the game does not like running BELOW 60Hz. I am running Windows 7 BETA and this does not currently allow to go above 59Hz. I used an application named Powerstrip - http://entechtaiwan.com/util/ps.shtm I then created a profile which Forced the 60Hz mode when the PES 2010 demo was launched. This the introduced tearing on the screen, soo... I used D3D Overrider from within the Rivatuner app - http://downloads.guru3d.com/RivaTuner-v2.24c-download-163.html I forced Vsync and Triple buffering and tearing was gone. Game now running VERY smooth. Many thanks to all who have helped.