I've just swapped GPU's from ATI HD4850 to Nvidia GeForce 9800GT.

Reason for the switch was problems in Softimage XSI 7 with the Radeon drivers. Houdini worked like a charm, though.

This time it's the other way around!!! :shock:

Now XSI works like a clock, but Houdini is not responsive.
The viewports are “laggy”. It takes almost a second for the SRT tools to react visually, than it “jumps” into place, making it impossible to model anything.

I use the latest drivers and have set the Nvidia 3D settings to all application controlled.

My other specs are:

Nvidia 9800GT 512MB DDR3
2x C2Duo E8400 3Ghz
4 GB Ram
Vista Business 64 (classic theme, no Aero)
ASUS P5Q Motherboard

Can't imagine what should be the cause for this, as the Nvidia drivers has better OpenGL support than the ATI drivers…

Any ideas out there???

:roll: