Hi Don, pulling the card was the only solution I could find. The GT 120 works OK on its own, but is underpowered enough to create other really inconvenient, but less serious problems.
I haven't gotten round to putting in a new card yet, but will do so soon, as the situation is unsustainable. I'm just not sure which card would best. Nvidia seems to have the upper hand when it comes to driver longevity though.
I put the Radeon in another machine where it seems to work fine, as long as I don't use Aperture.
At the moment I'm pulling in old DV tapes into iMovie without any problem. Not sure how much the card is called on for that though...
Will post a again if I have any luck.
Cheers,
Ian
PS: I saw a comment from Midiotlv where he mentions getting two monitors to work from the same card. I think I tried that unsuccessfully on the Radeon 6870, although I would probably have done it without taking the GT 120 out.
I'm not sure if the people who got the 5770's to work were using cards spec'd by Apple, but mine was a PC card that was flashed to work on the Mac Pro. I think this is possibly where my problems come from. Problem is, the Mac spec'd cards cost a small fortune, especially ones that work on the early 2008 - 3,1 machines... Even today, which is nuts!