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5870 Problem

strausd said:
So I just got my 12-core MP, yay!

However, I am trying to run an ACD 24", dell u2311h, and my tv at the same time. When I have all of them plugged in, the dell u2311h won't come up with anything. But when I unplug the tv form the MP, the u2311h comes up. Its like it can only run a max of 2 monitors. Is there a way to fix this?
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i just got same machine like yours and i connected some monitors i could get without using any adapters and everything seems fine (2x ACD 24 and HP w2408h). Also this 12 Core Mac Pro is a real bad ass 😱 working in Premiere CS5 or AE CS5 right know is smooth like cutting butter with knife :] now give me 27 ACD so i can see World Of Warcraft in 2560x1600 :] Radeon 5870 rocks ! 😀
 
sboerup said:
I thought we did post the reason why it's not working. Have you tried the active link cable from Apple?
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The $100 cable? That is only needed for a 30" display to be plugged in to MDP. There is no reason why I would need that for a 23" monitor that is already DVI... And it works fine, I just can't have the TV plugged in too...
 
strausd said:
The $100 cable? That is only needed for a 30" display to be plugged in to MDP. There is no reason why I would need that for a 23" monitor that is already DVI... And it works fine, I just can't have the TV plugged in too...
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I posted the link to the Apple support document for you on the first page. If you run three monitors, you must use TWO dual-link DVI cables.

It sucks, I know. I have three monitors also.
 
strausd said:
The $100 cable? That is only needed for a 30" display to be plugged in to MDP. There is no reason why I would need that for a 23" monitor that is already DVI... And it works fine, I just can't have the TV plugged in too...
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The you didn't read all the responses. I'm just as upset about this too 🙂

The dual-link cable is not just that, but also an "active" connection. Then cheaper adapter and other ones (like monoprice) are passive adapters. So what this means is that the apple 5879 only allows 2 passive connections via dvi . . . So the other requires an "active" cable which is only found in the expensive $100 cables. It's not the dual link, it's something else in the cable.

As others in this thread have shown, as soon as they used that adapter the three displays worked (where the 3 displays had at least 2 dvi).
 
sboerup said:
The you didn't read all the responses. I'm just as upset about this too 🙂

The dual-link cable is not just that, but also an "active" connection. Then cheaper adapter and other ones (like monoprice) are passive adapters. So what this means is that the apple 5879 only allows 2 passive connections via dvi . . . So the other requires an "active" cable which is only found in the expensive $100 cables. It's not the dual link, it's something else in the cable.

As others in this thread have shown, as soon as they used that adapter the three displays worked (where the 3 displays had at least 2 dvi).
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According to the Apple support page here:
http://support.apple.com/kb/HT4279?viewlocale=en_US
you need TWO Mini DisplayPort to Dual-Link DVI Adapters to run three DVI monitors.

I will know for sure next Tuesday or Wednesday. My machine arrives Mon or Tue and the adapters should arrive around that same time. I will post if I am able to get it to work with only one active cable.
 
strausd said:
Gosh, that really sucks. I don't wana have to spend $100 just for that...
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it will be cheaper to buy a gt120 from ebay and use that instead...
Im actually sort of in the same position, I have 4 monitors all dvi plus a tv, so Im already using 5870 + gt120, 2 monitors will be connected via dvi, 2 via passive adapters, and now I either have to get another gt120 or fork over 100$ for the active one to stream movies on tv 🙁 (of course I can just swap tv with one of the monitors when I do want to stream but that just doesnt sound right given the price paid for the MP already )
 
Just read the above link from apple, here's a screenshot:
5870displays.png


If you have 2 DVI displays, it says you CAN use either the standard MDP>DVI or the dual link . . . so, I'm hoping that I'll only need 1 Dual-link to use all of my 3 DVI displays . . . anyone else tried 3 DVI monitors with 1 dual-link adapter and one standard adapter? I ask because this Apple page seems to almost contradict itself with this statement just above the graphic:

"If you are using more than one Mini DisplayPort to Single-Link DVI adapter, only two displays are supported across the three ports. All other configurations are supported."

I'm holding on to my 2600XT since I'm unsure if I want to pony up for the adapters ($40 on ebay BTW) or just use the display. The extra GPU is going for $150 or so on eBay, so getting 2 dual-link might be cheaper via eBay.
 
Oh, and throwing in an nVidia GT 120 might not be the best idea, I've heard that mixing ATi and nVidia GPUs in the same system can cause problems . . . should work, but can be buggy.
 
sboerup said:
Just read the above link from apple, here's a screenshot:
5870displays.png


If you have 2 DVI displays, it says you CAN use either the standard MDP>DVI or the dual link . . . so, I'm hoping that I'll only need 1 Dual-link to use all of my 3 DVI displays . . . anyone else tried 3 DVI monitors with 1 dual-link adapter and one standard adapter? I ask because this Apple page seems to almost contradict itself with this statement just above the graphic:

"If you are using more than one Mini DisplayPort to Single-Link DVI adapter, only two displays are supported across the three ports. All other configurations are supported."

I'm holding on to my 2600XT since I'm unsure if I want to pony up for the adapters ($40 on ebay BTW) or just use the display. The extra GPU is going for $150 or so on eBay, so getting 2 dual-link might be cheaper via eBay.
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That says that if you have 2 MDPs and a dual link DVI you should be able to just connect them all without any adapters... Thats pretty much what I am doing, except its single link DVI and the TV is on HDMI to MDP.

That picture then goes against what other people said where I need to buy a $100 adapter. Am I missing something?
 
So, you have a Dell 23", an Apple 24" and an HDTV. Is your 24" ACD a newer one with the MDP port already? I'm also assuming your Dell is connecting via DVI, and your HDTV via HDMI (both with MDP > DVI/HDMI adapters)?

If so, then it sounds like if you want to use more than 1 MDP connection on the 5870, you'll need at least one Dual-link connection. Thats the way I understand it.
 
sboerup said:
So, you have a Dell 23", an Apple 24" and an HDTV. Is your 24" ACD a newer one with the MDP port already? I'm also assuming your Dell is connecting via DVI, and your HDTV via HDMI (both with MDP > DVI/HDMI adapters)?
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Ya, the 24" has MDP already. The dell one is connected to the dual link DVI on the 5870, however the monitor itself is only single link. And my TV is connected via an HDMI to MDP, no DVI adapters for the TV.
 
OK, I'd call Apple, but like the success of others in this thread, the easiest solution is to get the dual-link adapter. Sucks.

I just bought 2 on eBay for $40 each. Not so bad.
 
sboerup said:
OK, I'd call Apple, but like the success of others in this thread, the easiest solution is to get the dual-link adapter. Sucks.

I just bought 2 on eBay for $40 each. Not so bad.
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LOL...I did the exact same thing earlier today. Found them for 39.99 each plus a couple of dollars shipping.
 
I've spent two full days working on this myself plus an hour on the phone with AppleCare trying to get three DVI monitors working on my 2010 Mac Pro with a 5870. The short story is that you have to buy two of the $99 Mini DisplayPort to Dual-Link DVI Adapters to make that work. PITA.

I'm going to try reflashing an old 8800GT or hunting down another video card instead of spending $200 on the adapters. Although, the $40 eBay adapters sound promising - has anyone actually tested those and gotten three DVI monitors to work?

I just wrote down everything I learned about all the three monitor stuff here: http://blog.acceleroto.com/2010/08/...2010-mac-pro-with-3-monitors-read-this-first/

Hope this helps,
 
I posted this in the other thread about monitors:

I just got off the phone with Apple support regarding a similar issue I'm having with the U2311H. They were mentioning that if you're connecting three displays to the new Mac Pro, there's an extra "power cable" (not sure if that's proper terminology) inside the computer for the graphics card that must be connected in order to drive three displays. This is the first I've heard about this, so I thought I'd pass it along. I don't really know any more than that.

I'm no expert on this kind of thing, so I'm not sure if that's helpful.
 
The miniDP to HDMI for your TV is really no different from miniDP to DVI for a monitor short of the name and connectors; you need to get the dual-link adapter and then a DVI to HDMI adapter/cable. Apple does not explicitly list it, but this is implied.
 
Assuming, of course, that you're not planning to run two monitors on Display port. It probably isn't worth buying the card, otherwise...
 
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