Hi,

thanks, it's Mac Os X 10.6.8 on a mac Pro. I've read on this forum that 10.6.7 offers no advantages, so I'm not planning to upgrade this.

I'll upgrade to the latest Nvidia drivers. Things seem to have settled down (Catalyst made it through last night). The green lines problem was cured by forcibly installing the individual Nvidia drivers (the package installer said they weren't required).

Catalyst version is 4.40_m364_HD. Am I using the most appropriate version of Catalyst?

Thanks for the help!