2 video cards with HDX Mac Pro?

[rtcstudio]

Tried putting this question in the Pro Tools 11 section but only got one bite there, that really didn't help much.

I'm on a Pro Tools HDX (single card) rig. Signature is up to date.

Although the Mac Pro I have (June 2012 2x2.4 GHz 6-Core, 64 GB RAM) has an ATI RADEON HD 5770 card that is supposed to support 3 monitors, I can never get reliable use from 3 monitors.

I have a Sony Bravia 42" Monitor that is being fed by the HDMI output and I have an ACER 24" monitor that is being fed with a VGA adapter. It has the Digital input, but again, the most RELIABLE monitor set up with this Mac Pro is the one Sony HDMI monitor and one VGA monitor.

Whenever I try to hook up the 3rd Acer 24", it will work sometimes, and then sometimes it will not activate at startup, or it will go dark during use after an initial successful start up.

I've been on the Apple site, and this card seems picky if you are using the HDMI output. They for sure recommend that you do NOT use the Digital output for additional monitors. Seems like it is supposed to work with HDMI and 2 VGA, but I don't see that here.

AVID used to say DO NOT use a 2nd Video card in a Pro Tools rig. I was wondering if now, it might be okay to have an additional video card in my rig with the one HDX card.

After a search, there was one post of a user here that has 6 monitors on 2 ATI video cards in his rig, but no signature, no details.

Is it okay now-a-days to have a 2nd Video card in a Pro Tools rig? Especially an HDX PT HD rig? If so, specific cards would be appreciated!

THANKS!

[Craig F]

for a 3rd monitor on the ATI card you need to use an Active Adapter not the usual passive adapter you can find most any places.

Or you can use a Black Magic card in extended Desktop mode for a 3rd monitor

I remember the thread about the guy with 2 cards and he only had problems as I remember

[rtcstudio]

Originally Posted by craig f

for a 3rd monitor on the ati card you need to use an active adapter not the usual passive adapter you can find most any places.

thanks!!

[Hanswurstlsepp]

Originally Posted by Craig F

I remember the thread about the guy with 2 cards and he only had problems as I remember

I got no ATI cards, but 2 NVIDIAs. Hooked up 3 monitors since a couple of years.
No problems - not with PT8/9/10 & Magma chassis (was a HD6) neither with HDX1 so far.

1st card Apple Cinema display 30" and 24", 2nd card a tiny little old NEC 15".

[rtcstudio]

Craig, thanks, I solved all my problems using active adapters. Amazon Prime has 'em on sale.

Three monitors rock solid now.

;-)