[PyMOL] 3D stereo with nVidia K4200

Dear Pymol users
I would like to use Pymol (1.7.4)  with 3D stereo, so I bought a nVidia Quadro K4200, an asus VG278H and nVidia vision 2 kit ( with IR emitter) and I'm using Windows 7 Pro x64. 
I installed the latest nVidia driver for Quadro card (347.25) . In the nVidia control Panel for Pymol I set '' enable stereo '' to ON. In Pymol, when I click on display - Quad buffered, the light of the IR transmitter turn green but I get flickering and no 3D effect on the molecule. What is the issue ?
Cheers
Sam