Confirmed working with 200-series. :D
Interesting - I Just installed a new i7/920 rig with windows 7 x64 (Final) and my GTX285 with 190.63 drivers. My Th2Go is epic FAIL . only a 4080x900 resolution for triplewide will come up, everything else is "windows error". Powerdesk 2.05 (latest) and the latest (ati addition) firmware for the box is installed.
I contacted Matrox and got the response that they will not enter into any troubleshooting for the TH2GO on Windows 7, it only works on XP (all resolutions) and Vista under 182.5 driver , DX9 only.
Matrox flatly refused ANY kind of beta sofware availability and claimed NO support for W7, although their compatibility tool comes up all greeen lights.
So, where is this "BETA" powerdesk of which you speak? I'll try this and the 190.58 dirver (assuming I can locate)
I'm not certain if my setup is complicated by a second 9800GTX video card set to Phys-X.