ATI Radeon HD 5770 and 3 monitors : 2x mini DisplayPort to HDMI, 1x DVI-D to DVI-D

Not sure what your 12GB reference came from, but 16GB is the minimum that I would need to run on a 5,1. I mentioned OWC to say that "if" I went that route with OWC, I would have them ship it with 8GB on (1) stick, and then I'll add the 8GB that I would pull from this one for a total of 16GB.

Thanks Hatter, I'll update you after taking it for a spin over the weekend.

Enjoy your weekend

I can confirm that this (Grant's link to the amazon active DVI to mini display converter http://www.amazon.com/gp/product/B004071ZXA?psc=1&redirect=true&ref_=oh_aui_deta ilpage_o03_s00) worked. I used two of those plus the direct DVI connection to run 3 monitors, 2560X1600, 1920x1200, 1920x1200 w/ ATI Radeon HD 5770 card in my Mac Pro 5,1 - a big savings over the official apple recommendation. Thanks, Grant!

Thank YOU for posting your follow-up affirmation.

Glad you got that sorted out!

Someone had to! 🙂

Can ALSO confirm that by using 2 ACTIVE Minidisplay Port > DVI connectors and the single DVI connection on the 5770, 3 monitors is easily done.

Hey Grant,

I posted this recently in the forums but I thought I'd directly ask you, since you seem to know a lot!

I have a 5,1 Mac Pro. Specifically, a Mid 2010 2 x 2.4 GHz Quad-Core Intel Xeon model with 64 GB 1066 MHz DDR3 ECC memory running OS X 10.10.5.

I currently have two ATI Radeon HD 5770 1024 MB graphic cards, both stock, but I am looking to sell one to free up slots for other things.

My question is, I'd like to know if it's possible to run two 2k monitors ( currently looking at:http://www.newegg.com/Product/Product.aspx?Item=0JC-0009-00012 ) while also running 1080p on my Sony Bravia 40"?

I was thinking I'd go:

mDP to DP on 2k monitor #1

mDP to DP on 2k monitor #2

dual-link DVI to HDMI on Sony Bravia 40".

It should be noted that I'd like to have all monitors operating at a minimum refresh rate of 60Hz.

Do you think that would work, with or without active adaptors or anything else?

This article lays out the options in table form. Each display can be up to about the resolution of the Apple 30" cinema display (2560 by 1600).

Mac Pro (Early 2009), Mac Pro (Mid 2010), Mac Pro (Mid 2012): Supported display configurations - Apple Support

If you work better with rules than with tables, the rule is: any "legacy" displays beyond two require ACTIVE adapters. "legacy" displays means anything other than DisplayPort or Mini DisplayPort.

The table is interesting, but I guess it lacking the scenario I'm presenting...

There would need to be a box that said "Two Mini DisplayPort Displays and a DVI to HDMI 1080p display over 30-inches."

My guess is under "Dual-Link DVI" it could say several things like, "will not work" or "need special adapter."

That is the question mark I can't figure out. Is there even such a thing as a DVI to HDMI active adapter, and would I need it? I've read online that people advertise that they exist but really they don't.

So I'm still left wondering if what I'm asking for is too much for my card...

HDMI over 1920 by 1080p is very fussy to get working properly.

But if 1920 by 1080p is the resolution of your big TV set, that is just Single-Link DVI to HDMI and ordinary cables.

So do you think I should be ok then? The duo 2k monitors via mDP won't make the 1920x1080p hard to get on a 40" via DVI to HDMI? (all at at least 60Hz refresh?)

The screen size in inches matters not at all. The resolution is what matters, and 1920 by 1080p is "ordinary". No 30Hz BS, it should just work.

Each screen's resolution stands on its own -- one big one does not mean the next one has to be tiny. There is WAY more VRAM there than is needed just for display buffers. What is used up is "off-screen" redraw areas that can make the next (completely different) frame SNAP into view.

Thanks! You've been super helpful.

Time to go shopping.

Just took a bit of a leap and tried two of these quite inexpensive Active MiniDisplayPort to DVI adapter on my Radeon 5770.

Two of these adapters ($12 Cdn each) and plus one monitor directly connected to the card's DVI port allows three 1920x1080 monitors to come up nicely.

These are not externally powered (only powered from the MiniDisplayPort).

I tried using just one and it didn't seem to bring up three monitors -- had to use two of them (as previously stated in this thread, I believe).

Also - I noticed this seems to fix the trouble I was having waking the monitors up from sleep (at least so far).

http://www.ebay.ca/itm/161896740593?euid=216a5e436337424d973a22a4161acd8a&bu=430 33414782&cp=1&sojTags=bu=bu

Features:
100% Brand New! Quality is guaranteed.
Mini Display Port mini DP to DVI Active Converter connects mini Display Port enabled devices to DVI equipped 4K Ultra monitors, displays and HDTVs. It can support displays of up to 3840x2160 30 Hz HDTV PC graphics and is ideal for your office, home entertainment display, conference rooms, and more.

Specifications:
1 x 24+1 DVI Female Port
With PS171 Chipset, no external power supply
Support Audio output
Support Up to 10.8Gbps Bandwidth
Support AMD / ATI Eyefinity wide area technology to support multi-screen display.
Supports ATI Eyefinity screen display up to 6
EDID automatic recognition, support high-definition resolution of 1920 x 1080, 1920 x 1200
Up to (3840 x 2160) resolution output physical; 4K * 2K 30HZ
Easy PLUG & PLAY installation - No driver or software installation required!
Size: 6*4*1.8cm

Package Includes:
1 X DP to DVI adapter cable

wow, that's really inexpensive.

I use a talking number of about US$40 for typical ACTIVE adapters for up to 1920 wide.