4 Graphics Cards in 2010 Mac Pro

[Stephen23]

Hello Rumormongers,

I'm working on a theater event for which we need to run eight video projectors. Because of the way they run (rarely will they all be on at the same time), I believe it's going to be possible to run it all from one Mac Pro, but in looking at the Apple website this weekend, it looks like I might be wrong. In all the MP incarnations 2009 and previous, there was an option to install 4 graphics cards, but in the 2010 models, with the 5770 card, they only offer up the option of installing two. I have a few questions about this:

1. Does the 2010 Mac Pro have 4 PCI slots, or 3? Given that one comes with the basic graphics card installed, I'd hope it has three empty slots.

2. Is the reason Apple isn't offering the option of more than two 5770 cards one of internal power, physical space, or something else?

3. Assuming that the 5770 graphics cards will fit into the first two PCI slots (the 16x slots) - does anyone know if it would be possible to put two of the GT 120 cards or another older graphics card into the #3 and #4 slots and use them simultaneously?

For the record, and those who will chime in with various warnings - I've done this kind of thing before, and am aware of the various bottlenecks. As I noted, there are very few times that all the projectors will be running simultaneously, and we will be using Qlab, a professional video/sound program to run the show, along with three, or possibly four of the OWC SSDs to deliver the content. Essentially though, I am faced with a couple of choices about the machine, neither of which make me very happy:

Use a 2010 Mac Pro with two 5770 graphics cards, which means I have to buy four dual-DVI to minisplayport adapters ($100 each) in order to run 6 projectors - then still find a way to run two additional projectors.

Purchase a 2009 Mac Pro and outfit it with four of the GT 120 cards.

- I'm not thrilled about buying an older computer and especially not about purchasing very inferior cards to put into it, yet, from the information on the Apple website, it doesn't appear that the 2010 models can even handle this project.

Thanks in advance for answers to the above questions and other recommendations!

Stephen

 

[peskaa]

1. Same as the 2009, 4.

2. The 5770 needs a single power feed from the logic board, which only has two sockets. Ergo, max is two 5770s. The 2009 Mac Pros had the GT120 as an option, which needs no extra power, so you could fill the slots.

3. Yes you could put in two 5770s and then add a GT120 (3+3+2=8). Or, buy with a single 5770, find four GT120s for cheap and swap out the 5770.


4. You don't need the Apple dual-link DVI adapter. All you need is a third-party active MDP to DVI adapter, which is far less than the Apple. Note this is not the cheap adapter Apple sell, as this isn't active.

 

[Mackilroy]

If you're thinking of the adapters that I think you are, those are dual-link DVI, not actual dual-DVI adapters. Also, the 5770 supports up to three monitors, so two 5770s can run six.

 

[goMac]

The 2010's can run the GT 120. No need to purchase an older Mac Pro.

The GT 120's are not super gaming cards, but they aren't slow either. They're a little short of the GeForce 8800, which isn't too shabby.

 

[WardC]

Yes, you can run four GT120 card from the 2010 Mac Pro, no need to install a power feed from the logic board. Each GT120 will power two DVI monitors.

GT120s can probably be had now for under $100 each if you can find them.

Good luck.

 

[Stephen23]

Mack - Yes, sorry. I meant to type dual-link - not dual DVI. Two 5770's gives me 6 projectors (three each), which is what I wrote as one of my options. But I need eight, total.

peskaa - thanks for the quick answers. These are basically what I expected, but it's nice to get hard information. Thanks very much for the tip on the third party active adapters. I knew I couldn't do it with the cheap(er) single-link adapters from Apple, but purchasing four of the expensive dual-link for an additional $400 or so on top of everything else was going to annoy me a lot.

Ward/GoMac - Thanks for the tips. This will only ever be a video server machine, so gaming isn't really a concern, but graphics memory and performance are a consideration, so it's good to hear that they aren't all that slow. Most likely I will go with one of the new machines, leave the existing 5770 to use for the most intensive channels, and fill the rest of the slots with the cheaper GT 120's. The only concern at that point will be whether the 4x slots prove to be a bottleneck running two projectors each. I'm hoping that by placing my channels strategically, so that the 4x don't often have to support both projectors at once, I might be able to get away with it.

 

[alust2013]

Will any of the projectors be showing the same thing as another? In that case, you could use a splitter and run both from one port. Each 5770 has two MDP and one DVI, so if you could split two of them, you would have a total of 8 outputs, with two pairs of duplicates.

Also, what resolution are your projectors?

 

[Stephen23]

hi alust,

Those considerations are already included here. In fact, we will be running 12 total projectors, but with only 7 distinct channels of video, plus one output for the main system screen. Four of those 7 video projection signals will be running into powered VGA splitters to multiple projectors.

The projectors will be standard XVGA projectors, but the animator has indicated that she will be using 800 x 600 resolution due to the difficulty/time of rendering so much content. I'm not thrilled with that decision from an artistic standpoint, but it certainly helps me in terms of not needing quite as much bandwidth to handle it.

 

[Stephen23]

Doing some other reading on these forums, it appears that I would possibly NOT be able to go with the 2 x 5770 and 2 x GT 120 setup due to the physical size of the 5770s. The one in slot #2 would physically block the #3 slot, since it's not a double wide.

Can anyone confirm/refute this?

Of course I noticed this just after I'd sent the recommendations to the production manager to do exactly that. It looks like I will need to go with 1 x 5770 and 3 x GT 120s instead.

 

[Transporteur]

Doing some other reading on these forums, it appears that I would possibly NOT be able to go with the 2 x 5770 and 2 x GT 120 setup due to the physical size of the 5770s. The one in slot #2 would physically block the #3 slot, since it's not a double wide.

Can anyone confirm/refute this?

That is correct. Two double-wide cards leave a single PCIe slot available.
The maximum amount of outputs with the stock Apple cards is 9 (1 5770/5870 + 3 GT120's).

 

[goMac]

2x 5770s and 1x GT 120 would give you 8 outputs. Not sure why you'd need to do 1x 5770 and 3x 120.

Edit: Optionally, if you're not going to be running them all at once, why not use switches?

 

[Stephen23]

GoMac,

The reasoning is that I am trying to take advantage of all four slots. Bandwidth is going to be an issue, and there is a good chance these guys are going to want even more out of this system once they get into rehearsal, so I am trying to spread that load, and leave myself the option of adding a matrox triple head to the 5770 if needed. If I am already running three channels out of it, it's going to have a hard time doing anything more.

While we will rarely be using all the projectors at the same time, there will be a few times that we do. It might end up having to be still images or something, but we will need that option. Manual switching is not an option!

In quizzing them about what they are trying to do, it's already coming to light that they may actually want more than what I've described here. I think maybe that they have been told that it was possible to double up images in a way that it is not, so I'm already wondering if I need to jump to two 5770s and multiple matrox triple-heads. Anyone tried that set-up?

I'm going to have to buy an industrial size fan and a dry ice bath for this thing!

thanks,

Stephen

 

[goMac]

GoMac,

The reasoning is that I am trying to take advantage of all four slots. Bandwidth is going to be an issue, and there is a good chance these guys are going to want even more out of this system once they get into rehearsal, so I am trying to spread that load, and leave myself the option of adding a matrox triple head to the 5770 if needed. If I am already running three channels out of it, it's going to have a hard time doing anything more.

While we will rarely be using all the projectors at the same time, there will be a few times that we do. It might end up having to be still images or something, but we will need that option. Manual switching is not an option!

In quizzing them about what they are trying to do, it's already coming to light that they may actually want more than what I've described here. I think maybe that they have been told that it was possible to double up images in a way that it is not, so I'm already wondering if I need to jump to two 5770s and multiple matrox triple-heads. Anyone tried that set-up?

I'm going to have to buy an industrial size fan and a dry ice bath for this thing!

thanks,

Stephen

You should have more than enough bandwidth over three slots to power 3 1080p displays. A 16x slot can more than easily power 3 1080p displays. Remember, a 16x slot can power 3 30" Cinema Displays no issue, which are even higher res.

I wouldn't worry about bandwidth of the PCI slots.

It sounds like what you might really want are multiple Mac Minis, however.

 

[Transporteur]

I think maybe that they have been told that it was possible to double up images in a way that it is not, so I'm already wondering if I need to jump to two 5770s and multiple matrox triple-heads. Anyone tried that set-up?

Keep in mind that the tripleHead2Go will make one large display, rather than three separate ones. So with two 5770s you'll still end up with 6 individual displays.

I reckon you require OS X, right?

 

[Stephen23]

Yes, Mac is required, as Qlab is the show control program. The next option would be a much more expensive dedicated video server, but these guys just don't have that kind of money.

goMac - when doing sound installations with Qlab, minis are the weapon of choice, but their integrated graphics make them very poor options for video installations. The nice thing about Mac Pros is that you can run multiple hard drives into multiple graphics cards with a single processor, which is ideal, as the drives and the graphics bandwidth are the limiters on any system.

In theory, you're right about the ability of a single graphics card to run three 30" monitors, but in practice (this is not the first one of these I've done), graphics cards, bandwidth, and getting the stream to them from the drives are all big chokepoints in running video for live events. My best guess about why is that small hiccups on your three monitor system at home go unnoticed while a hiccup on a 20' tall video screen in front of a crowd of 2000 does not.

Transporteur - I've used the Matrox heads before, so yea, I have a good feel for what they can do and how they work - I've just never tried to run four video outputs from a single card before, and I haven't used one of the 5770s yet - all I know is how it compares in various tests on barefeats and other mac performance websites. I was leaving the matrox heads as my reserve, both because of added complexity and expense, but these guys just took that away from me today.

What I'm thinking now, inlight of the new information that's come at me today is running two 5770s, with each one supporting two Matrox heads, for a total of 4 separate video channels out of each card. I'll add one GT120 in the last remaining slot, which will run the system monitor with Qlab. That will give me 9 total outs, and if necessary, I can still use the third out on each of the 5770s. That will almost certainly choke if we try to run all of them at once with video, but I think that with still images that just come up and stay, we might get away with it.

 

[WardC]

If it was me, I would go with one 5770 and 3 GT 120s. The GT 120 is a relatively cheap card that can power two monitors very well for any basic or video display purposes. Unless you are gaming on eight displays using max settings, you would do fine with this setup. You can get three GT 120s for around $200.

 

[goMac]

In theory, you're right about the ability of a single graphics card to run three 30" monitors, but in practice (this is not the first one of these I've done), graphics cards, bandwidth, and getting the stream to them from the drives are all big chokepoints in running video for live events. My best guess about why is that small hiccups on your three monitor system at home go unnoticed while a hiccup on a 20' tall video screen in front of a crowd of 2000 does not.

Are you sure? ATI makes 6 display cards designed for exactly this kind of work that run over one 16x bus. (Sadly Windows only)

A 16x bus can actually push a LOT of data. 8000 MB/s which is enough for about 1280 1080p frames a second... Which should be able to handle 42 displays at once... (I do video work for a living, specifically dealing in real time input/output.) Even if you're hammering on VRAM, it should be able to keep up just fine with 3 displays.

Slower cards might have issues, but the 5770/5870 were designed for pretty much just this sort of thing.

If you are worried about graphics bandwidth, however, the Mac Mini is actually a much better option in since there actually is no bandwidth to be concerned about as there is no extra path to the GPU in since the GPU sits on the mainbridge. I know it sounds backwards, but in bandwidth intensive situations, I've actually benched the 9400m beating other chipsets in my GPU research.

Linking a bunch of Minis together might be a PITA, though, but a Mini GPU is actually pretty capable. Just a thought.

 

[snberk103]

Interesting discussion.

It seems to me that Qlab might be a good source of information. They've probably worked (via other presenters) with all sorts of hardware combinations. I'd call and see if they have any thing to add to the discussion.

 

[Stephen23]

goMac - I've never specifically used Minis for video work, but other Qlab users have reported having issues with them. I do use my 2008 (black) MacBook for video occasionally, and while I don't really have issues with it running a single projector in addition to it's screen, I have tapped it out with high def video, and I don't think it could handle running a matrox triple or dual head. Given that experience I discounted using the minis, despite the fact that they would be far easier to take on tour, and I like the redundancy of multiple machines rather than one.

In actuality, running multiple machines with Qlab is a breeze. Not much more work than running one, and they just use midi-over-ethernet, so it's not any more expense, other than the cost of more computers. If I had my way, we'd be buying around 5 or 6 minis instead of one Mac Pro, but that's a cost difference of around a grand or more. Plus buying 5 SSDs instead of three, etc.

 

[Stephen23]

snberk - I'm on the Qlab users forum/email list, so am pretty up to date with what the various power users are doing... Chris, the guy who wrote the program, and the other users on that forum are super helpful, but in terms of video, at least from what I read there, I seem to be pushing it about as hard as anyone. :/

Frankly, there is a good chance that if this project comes off anything like planned, it will end up on the Qlab website. lol.

 

[goMac]

It might be worth just moving to Windows and using an Eyefinity card.

 

[Stephen23]

Even if I wanted to, which I don't - this is a Mac Rumors forum, after all; jumping to Windows wouldn't be an option. It would mean starting from scratch with new software, and buying software that has the same or similar functionality as Qlab would cost nearly as much as the computer itself. Plus there is the fact that while I can get around in the Windows OS, I don't have the expertise to do true troubleshooting when things go wrong, and if I'm pushing a Mac system this hard, lord knows that Windows isn't exactly going to sail through it.

Thanks for the information, everyone... I think I've got a pretty good plan, and we'll see how it works out.

Stephen

 

[WardC]

Look for the GT120 on eBay...I see them periodically for sale, usually in the $50 - $100 range per card. Each card can drive two monitors at up to 2560x1600. Decent card for basic use, if you don't need to do any serious gaming or 3D displays.

GT120 is compatible with all 2009/2010 Mac Pros and does not require its own power source connection on the motherboard, it draws all its power from the PCI slot.

 

[The-Pro]

You can install 3 5770's aswell. Each require one power lead so you get a 6 pin splitter and you can connect all three 5770's. However wont be able to install HDD's in Bays 3 and 4 as the GPU in slot 2 will cover slot 3, and the GPU in slot 4 will extend into the HDD bays.
I saw a vid of someone using 2 5870 and gaming quite intensively, (hes using two 6 pin splitters) hes had that setup for some time apparently and has not had any problems despite drawing double then electricity than what apple said it can to from the ports.

3 5770's will be more powerful than any of the other options. 3GB VRAM compared to 2GB (4 GT 120's) or 2.5GB (5770, 3 GT 120 OR 2 5770 and 1 GT 120)
Sadly you would need 6 adapters or cables compared to 4 or 5 with the other options.

All you need is a third-party active MDP to DVI adapter, which is far less than the Apple. Note this is not the cheap adapter Apple sell, as this isn't active.

Thanks very much for the tip on the third party active adapters.

I have a question What does that active and non active thing mean?? and how does it effect performance etc. I use many screens with my mac pro and i use apples single link adapters for the FULL HD ones and the Dual Link DVI ones for my 1600p screen. wondering if there is a different way because those dual link adapter are extremely annoying and have so many bugs (they are s*** in my opinion )

cheers

 

[minifridge1138]

You could use 4 GT 120 cards to get 8 screens running.
That's the simplest way. The cards do not require external power.

People bash the GT120, but I think its a very good little card.
It had no problem running my HD monitor and a 1440X900 secondary screen.
It even handled light gaming well (WoW at mid-to-high settings).

Of course the 5770 and 5870 are better, but that doesn't mean the GT120 is bad.

I have a GT120 and I'd be happy to trade it for the 5770 that came in your 2010 MP