Dual Display Issues - NO SIGNAL

[Gh0stKiller]

Hey everyone,

Long-time reader here, first-time poster. This forum helped a lot with my recent decision to upgrade to the hexacore Mac Pro, but I'm already having a little bit of trouble with it. Sorry to take advantage of you guys like this, but I figured you were the best place to turn before I have to start calling Apple Support.

So, I just set up my hexacore Mac Pro with stock ram and the ATi 5870. To go along with it, I purchased two Dell u2311h monitors from Dell so that I could finally have dual displays. I then purchased two 6' minidisplayport to displayport cables from Monoprice. Also went with the Apple wireless keyboard and Magic Mouse.

Upon initial start-up, everything worked fine. The monitors needed to be calibrated, but dual display mode worked perfectly without any extra steps. I had some fun messing around for a little bit and then decided to take a break. I put the computer to sleep.

I came back 15 minutes later (couldn't stay away for long), and clicked the mouse to wake the computer back up. I heard the tower humming, but the monitors stayed black. I tapped the keyboard. Still black. Assuming it was some issue I wasn't prepared for with the wireless peripherals, I futzed around with them for a while and had no luck. Still not image on the monitors. I turned the monitors off and then back on only to get an error message explaining that the monitor was in Power Save mode. Some further exploration revealed that the monitors were allegedly getting NO SIGNAL from the computer.

Restarting didn't help any. The only thing that has "worked" is shutting down the computer and connecting a single monitor through the DVI-D cable that came with it. Both monitors work, but obviously not together. In doing some research, I've found some threads on different sites about people having similar dual display issues attributed to faulty graphics cards. I certainly hope this isn't the case, but aside from two faulty cables (and I've never had any trouble with Monoprice cables in the past), I'm at a loss for what the problem might be. It seems odd that dual displays would work briefly only to fail after going to sleep for 15 minutes.

Sorry if this is the dumbest question ever. Is there something stupid that I'm doing wrong? Anyone have any insight?

Any guidance you guys can provide would be greatly appreciated. Thanks in advance!

[Vylen]

I have a similar issue... 3 monitors, Samsung by DVI and 2x U2311H by MDP. On the rare occasion on cold-booting no displays get driven if all are plugged in, solved by plugging in only the Samsung and then plugging in the Dell monitors.

Oh, and my main monitor is one of the Dell's... so it has to power that one up first and give it a signal on boot

It's "nice" to see someone here is having similar problems. Can you link me to the other threads you found? I'd like to read them for myself.

[Gh0stKiller]

Here's a couple of threads where users have more or less concluded that their "no signal" issues were due to a faulty graphics card. Obviously, these don't pertain specifically to the 2010 Mac Pros or the Dell monitors, but as the issues are so similar, I figured the diagnosis is at least worth looking into.

http://discussions.info.apple.com/message.jspa?messageID=7938254

http://forums.macworld.com/index.php?/topic/107774-mac-pro-gpu-no-signal-after-display-resolution-change/

That's interesting that you're also having problems specifically with the U2311h. I wonder how much that has to do with it.

New info: Like I said earlier, my monitor wakes up from sleep mode normally as long as its connected through DVI-D. I just tried connecting the minidisplayport to displayport cable while I was running through DVI-D and then switching the input. Both monitors now work fine in dual display mode. Obviously, this means that it is not an issue with the cables.

[Vylen]

I think i'll wait to see if other people have problems either with dell or non-dell monitors... I haven't put this machine to sleep so I can't say if i do have exactly the same problem.

It's only happened twice to me... if it happens again, maybe ill try reseating the card/power... I dunno, heh.

[Gh0stKiller]

I'm going to try updating the graphics card drivers tonight and see if that helps any.

[jenzjen]

No problems here; I have a hex/5870 driving 3 Dell U2410s (2 via MDP to DP cable, 1 DVI-D).

[Vylen]

No problems here; I have a hex/5870 driving 3 Dell U2410s (2 via MDP to DP cable, 1 DVI-D).

Which one is your "main" monitor? i.e. the monitor that shows the grey bootup screen. If it isn't already, try set it to, say, the right-most MDP and do a cold boot?

[eponym]

I also have u2311h running via a mini DP to full DP cable from Monoprice. But it's the 5770 (and only 1 monitor at the moment). Haven't had any issues.

It's hard to say what might be the cause. Dell gear can be finicky. Could be bad port on one display screwing up signals. Could be bad cables. Could be a faulty card. Bad firmware....etc

Just some clarification: do you also turn off your displays after you sleep the Mac?

[Mr. Anderson]

I'm going to try updating the graphics car drivers tonight and see if that helps any.


Where do you find the drivers for the cards - I'm having a different issue with my new MacPro, but I'm thinking updating/reinstalling the drivers might fix things.

D

[Gh0stKiller]

Just some clarification: do you also turn off your displays after you sleep the Mac?

No, they automatically went into power save mode.

[Gh0stKiller]

Where do you find the drivers for the cards - I'm having a different issue with my new MacPro, but I'm thinking updating/reinstalling the drivers might fix things.

D

I actually haven't looked yet. At work right now. I'll have to try and tackle it when I get home tonight.

[Gh0stKiller]

No problems here; I have a hex/5870 driving 3 Dell U2410s (2 via MDP to DP cable, 1 DVI-D).

Can I ask where your MDP to DP cables came from?

[Gh0stKiller]

It's hard to say what might be the cause. Dell gear can be finicky. Could be bad port on one display screwing up signals. Could be bad cables. Could be a faulty card. Bad firmware....etc


I've pretty much ruled out the monitors and/or the cables as the culprit. They both seem to work fine independently. It also would be very odd that I just happened to receive two monitors with a bad displayport. I could be wrong, however.

For lack of a more technically precise way to put it, it seems to me like the minidisplayports on the computer are not "waking up" from sleep mode.

[jenzjen]

Can I ask where your MDP to DP cables came from?

Monoprice ... http://www.monoprice.com/products/subdepartment.asp?c_id=102&cp_id=10246&cs_id=1024606

[jenzjen]

Which one is your "main" monitor? i.e. the monitor that shows the grey bootup screen. If it isn't already, try set it to, say, the right-most MDP and do a cold boot?

When I was setting it up, I had both MDP ports set as my "main" LCD at different times, so I did boot it cold off both MDP ports but have always had all 3 monitors connected.

[Gh0stKiller]

Monoprice ... http://www.monoprice.com/products/subdepartment.asp?c_id=102&cp_id=10246&cs_id=1024606

Cool. I have the same ones, which further confirms that my cables are probably not to blame.

[Gh0stKiller]

Found this on the Dell support forums...

http://en.community.dell.com/support-forums/peripherals/f/3529/p/19339056/19722024.aspx#19722024

The thread above pertains mostly to the Dell U2711, but as I understand it, the U2711 and U2311h are very similar, as denoted by the similar model numbers.

[wally21]

So I've hooked up my two u2711's to my 12-core 2.93Ghz system with a 5870 graphics card.

I used the displayport -> mini-displayport cables from Circuit Assembly (http://estore.circuitassembly.com/products/Mini-Displayport-to-Displayport-Adapter-Cable.html).

These cables seemed to be of a better quality than the monoprice ones.

I haven't had any issues yet. I'll keep you posted if I do.

[Framedvision]

So I have two U2711 monitors and they are both plugged into the mini display ports... When I boot, I get nothing. It's interesting to not that if you screen share your macpro, (i screen share with iteleport on my ipad) you can see that osx has booted normally but if you go to system profiler and look at the graphics section, it will say No Information Available. The only way I am able to get the monitors to initialize is to turn of the computer completely, and then plug in ONLY the Dual link DVI of one monitor, wait for the computer to boot up fully, then unplug the dual link and plug in the two display ports to mini display ports. Then it work fine unless I put the computer to sleep. I can replicate this every time and it's alway the same. It's worth noting that I am writing this because I just got home from replacing the graphics card with a brand new one from the apple store, they had to order it, SAME problem. So It's Definitely an issue with either, 5870, the dell U2711's, or the cables from monoprice. I am going to try and order the cables that wally21 suggested from Circuit assembly.

I REALLY hope this works.

Does anybody have any other insight into this problem?

[Gh0stKiller]

So I have two U2711 monitors and they are both plugged into the mini display ports... When I boot, I get nothing. It's interesting to not that if you screen share your macpro, (i screen share with iteleport on my ipad) you can see that osx has booted normally but if you go to system profiler and look at the graphics section, it will say No Information Available. The only way I am able to get the monitors to initialize is to turn of the computer completely, and then plug in ONLY the Dual link DVI of one monitor, wait for the computer to boot up fully, then unplug the dual link and plug in the two display ports to mini display ports. Then it work fine unless I put the computer to sleep. I can replicate this every time and it's alway the same. It's worth noting that I am writing this because I just got home from replacing the graphics card with a brand new one from the apple store, they had to order it, SAME problem. So It's Definitely an issue with either, 5870, the dell U2711's, or the cables from monoprice. I am going to try and order the cables that wally21 suggested from Circuit assembly.

I REALLY hope this works.

Does anybody have any other insight into this problem?

Damn, that really bums me out. I am taking mine into the Apple Store this evening so they can take a look at the graphics card.

Over the phone, they told me to try using two of the Apple minidisplayport to Single-link DVI-D adapters. They did not work. Got no signal whatsoever on the second monitor. For me, this pretty much indicated that the 5870 must be the culprit...but if they replaced yours and it still has the same problem, now I'm not so sure. Maybe it's possible you just got two bad graphics cards?

I'm really sick of playing this game. Hopefully, I'll have better luck than you did with the Genius bar(no offense).

[Gh0stKiller]

So I have two U2711 monitors and they are both plugged into the mini display ports... When I boot, I get nothing. It's interesting to not that if you screen share your macpro, (i screen share with iteleport on my ipad) you can see that osx has booted normally but if you go to system profiler and look at the graphics section, it will say No Information Available. The only way I am able to get the monitors to initialize is to turn of the computer completely, and then plug in ONLY the Dual link DVI of one monitor, wait for the computer to boot up fully, then unplug the dual link and plug in the two display ports to mini display ports. Then it work fine unless I put the computer to sleep. I can replicate this every time and it's alway the same. It's worth noting that I am writing this because I just got home from replacing the graphics card with a brand new one from the apple store, they had to order it, SAME problem. So It's Definitely an issue with either, 5870, the dell U2711's, or the cables from monoprice. I am going to try and order the cables that wally21 suggested from Circuit assembly.

I REALLY hope this works.

Does anybody have any other insight into this problem?

BTW, did you see this?

http://en.community.dell.com/support....aspx#19722024

[Framedvision]

Ghostkiller, I really hope you do have better luck. Just a heads up, they will have to order the card card since they do not have stock of them yet. I truly hope you have better luck because then at least we know there is a solution. Meanwhile, I ordered the circuit assembly cables to see if that helps. Just know your not alone now in the quest for a solution... And I will not rest to I get a solution. Good luck guys!

By the way, the link above didn't work.

[Gh0stKiller]

Ghostkiller, I really hope you do have better luck. Just a heads up, they will have to order the card card since they do not have stock of them yet. I truly hope you have better luck because then at least we know there is a solution. Meanwhile, I ordered the circuit assembly cables to see if that helps. Just know your not alone now in the quest for a solution... And I will not rest to I get a solution. Good luck guys!

By the way, the link above didn't work.

Thanks for the well wishes, my man.

I did in fact have better luck. I owe my computer an apology. There is nothing wrong with the graphics card. I lugged the whole thing in to the Genius Bar on Friday and the very friendly guy who helped me had two monitors running fine in about a minute. Putting them to sleep, waking them back, everything worked great, it just took a little bit longer for the secondary monitor to come around.

I now have both monitors working through Apple's minidisplayport to DVI-D adaptors.

This means it's either the Monoprice cables or the monitors themselves. He didn't have a way to test the cables since they didn't have any displayport monitors available. Obviously, I didn't bring the monitors with me.

My suspicion would be that maybe there was nothing wrong with your orignal graphics card either. Maybe the Genius that helped you didn't test it fully before he made the diagnosis, although obviously I wasn't there.

The articled I attempted to link you to was a thread on Dell support forums where users were reporting basically the exact same problem you and I were having, specifically with the Dell U2711. They had eventually concluded that the monitors drop the displayport connection when they go into power save mode, but then are unable to reestablish it without a restart.

I'm not yet sure if it's worth it to me to return the monitors due to faulty displayports. I'm definitely thinking it over.

Let me know if those new cables work any better. It would be the easiest solution, that's for sure.

[b.lam]

Hi everybody,

it seems that the displayport issue also occurs when using only one display.

I have a NEC MultiSync EA231WMi and the 2010 Mac Pro with the 5870. My odysee with this issue started with WoW:

The display is delivered with a DVI cable, so I first used this one. But when starting WoW in fullscreen/maxed window mode, the display resolution was set from 1080p to 1080i. I could set the resolution back to 1080p via the system settings, but it was annoying. After doing some research I found some information that someone had the same issue with a 2008 Mac Pro/Radeon 4870 when starting City of Heroes and he solved it by using a MiniDisplayPort to DisplayPort cable. Therefore I bought such a cable from DeLock via Amazon.
When I got it, I first tried the MDP right next to the DVI but I got no signal. Then I tried the other one and it worked, but it was very sensitive to any motion on the Mac Pro side. A slightest touch and the signal disappeared (why the heck are they using MDP at all? There's enough space for 2 DP and 1 DVI plug and the MDP seems very fragile to me). This worked for about 1.5 weeks (and btw, it did not solve the resolution issue with WoW :-/).

A few minutes ago, I woke my Mac from sleep and got no signal on the DisplayPort. I tried everything from shutting down and unplugging the display for 30 seconds from power supply, trying also the other MDP interface on the graphics card. No luck. It seems as if the DisplayPorts don't work any more. DVI still works.

[Framedvision]

Because I too owe my computer an apology. The first graphics card I'm sure as fine because the replacement does the same thing. I actually took one of my u2711's in the first time. Here is the funny part, it works flawlessly via Mac pro 4870 mdp to dp but not with the 5870. So it's a combination of something of 5870 AND Dell. But let me get this straight, you purchased one mdp to d-link dvi and the other monitor is just plugged into the dvi correct? And that works fine?

By the way, new circuit assembly cables will be in tomorrow, will let u know if they work.

[Framedvision]

So I've hooked up my two u2711's to my 12-core 2.93Ghz system with a 5870 graphics card.

I used the displayport -> mini-displayport cables from Circuit Assembly (http://estore.circuitassembly.com/products/Mini-Displayport-to-Displayport-Adapter-Cable.html).

These cables seemed to be of a better quality than the monoprice ones.

I haven't had any issues yet. I'll keep you posted if I do.

To ANYONE who has had this issue other than myself and GhostKiller, THERE IS A SOLUTION!!!! GhostKiller, your solution to use apple's DL-converter to MDP is a good but expensive solution. I want to thank wally21 for silently solving our problem. IT IS IN FACT THE MONOPRICE CABLES!!!!!! I purchased the circuit assembly 3 meter cables and I have restarted my computer 4 times now, put it to sleep, woke it back up, unplugged it, let it sit, turned it back on, etc... AND FLAWLESS! Just like it is supposed to! I am confirming that the the MONOPRICE CABLES LOSE THE LINK BETWEEN THE 5870 and the DELL U2711's. The Circuit Assembly cables DO NOT. I'm SO GLAD! No my poor computer can get some sleep in it's brand new home for the first time... WITHOUT GOING BLIND WHEN WAKING UP! :cool:

[Vylen]

Maybe the place I bought my cables from (Australian Mac Store) use the same cables from Monoprice...

The only common thing i can see between my cables and Monoprice cables is that only support DisplayPort 1.1 (no audio).

Maybe one of you can read off what the Monoprice cables have written on them? Mine has "DisplayPort E301195 AWM STYLE 20276 80C 30V VW-1 PAK HENG"

Dunno if the CA cables support newer DP specification... and if it's the reason for the issues.

Anyway... it's good to know that it's just the cables... but slightly annoying since it's sort of a waste of money >_>

[Gh0stKiller]

To ANYONE who has had this issue other than myself and GhostKiller, THERE IS A SOLUTION!!!! GhostKiller, your solution to use apple's DL-converter to MDP is a good but expensive solution. I want to thank wally21 for silently solving our problem. IT IS IN FACT THE MONOPRICE CABLES!!!!!! I purchased the circuit assembly 3 meter cables and I have restarted my computer 4 times now, put it to sleep, woke it back up, unplugged it, let it sit, turned it back on, etc... AND FLAWLESS! Just like it is supposed to! I am confirming that the the MONOPRICE CABLES LOSE THE LINK BETWEEN THE 5870 and the DELL U2711's. The Circuit Assembly cables DO NOT. I'm SO GLAD! No my poor computer can get some sleep in it's brand new home for the first time... WITHOUT GOING BLIND WHEN WAKING UP! :cool:

Huzzah! Thanks for the update, buddy! This is very good news. Much easier solution than sending my monitors back.

Ordering the new cables now!

EDIT: Damn, the Circuit Assembly cables only got up to 5', which I'm not sure is long enough for my needs. I'm going to purchase some from Amazon by a company called StarTech. Hopefully, the results will be the same.

[Gh0stKiller]

Hi everybody,

it seems that the displayport issue also occurs when using only one display.

I have a NEC MultiSync EA231WMi and the 2010 Mac Pro with the 5870. My odysee with this issue started with WoW:

The display is delivered with a DVI cable, so I first used this one. But when starting WoW in fullscreen/maxed window mode, the display resolution was set from 1080p to 1080i. I could set the resolution back to 1080p via the system settings, but it was annoying. After doing some research I found some information that someone had the same issue with a 2008 Mac Pro/Radeon 4870 when starting City of Heroes and he solved it by using a MiniDisplayPort to DisplayPort cable. Therefore I bought such a cable from DeLock via Amazon.
When I got it, I first tried the MDP right next to the DVI but I got no signal. Then I tried the other one and it worked, but it was very sensitive to any motion on the Mac Pro side. A slightest touch and the signal disappeared (why the heck are they using MDP at all? There's enough space for 2 DP and 1 DVI plug and the MDP seems very fragile to me). This worked for about 1.5 weeks (and btw, it did not solve the resolution issue with WoW :-/).

A few minutes ago, I woke my Mac from sleep and got no signal on the DisplayPort. I tried everything from shutting down and unplugging the display for 30 seconds from power supply, trying also the other MDP interface on the graphics card. No luck. It seems as if the DisplayPorts don't work any more. DVI still works.

Your issue seems a bit different. If I had to chance a guess, it sounds like you have faulty MDPs on your machine. I would recommend taking it in the the Apple Store and getting them to test it out.

From personal experience with school computers, sometimes the ports on the Mac Pro just get messed up. There were a dozen Mac Pros at my campus editing lab, and each one of them had a broken headphone jack and at least one firewire port that would randomly stop working.

The weirdest part is the 1080i/1080p issue. Not really sure why it would be defaulting to that.

[Framedvision]

Just in case it was an oversight, The circuit assembly cables are in METERS so you can get a 5 meter which goes up to 16 feet. But maybe you do need more than 16 feet. Just thought I might help. ALSO, My old MONOPRICE cables do in fact read, (E301195 AWM STYLE 20276 80c 30v VW-1 PAK HENG) Those are the monoprice ones and those DO NOT WORK with the Dell u2711 / ATI 5870 config.

The ones that DO WORK say, (E74020-C AWM STYLE 20276 80c 30V VW-1 www.circuitassembly.com)

Great job everyone for the persistence

[Vylen]

Just in case it was an oversight, The circuit assembly cables are in METERS so you can get a 5 meter which goes up to 16 feet. But maybe you do need more than 16 feet. Just thought I might help. ALSO, My old MONOPRICE cables do in fact read, (E301195 AWM STYLE 20276 80c 30v VW-1 PAK HENG) Those are the monoprice ones and those DO NOT WORK with the Dell u2711 / ATI 5870 config.

The ones that DO WORK say, (E74020-C AWM STYLE 20276 80c 30V VW-1 www.circuitassembly.com)

Great job everyone for the persistence

Well, awesome stuff for the cable confirmation... I guess I should buy some cables from CA then to replace these...

[wally21]

Hey, glad I could be of help. Someone over at HardForum gave me the link to Circuit Assembly, else I probably would have ordered the monoprice ones and been in the same boat as you guys. I like that CA actually manufactures their cables and adapters.

[Gh0stKiller]

Just in case it was an oversight, The circuit assembly cables are in METERS so you can get a 5 meter which goes up to 16 feet.

Heh, yeah. That was an oversight. Damn the metric system.

Oh well. Hopefully the ones I ordered from Amazon work out.

[Vylen]

Hey, glad I could be of help. Someone over at HardForum gave me the link to Circuit Assembly, else I probably would have ordered the monoprice ones and been in the same boat as you guys. I like that CA actually manufactures their cables and adapters.

I like that CA sells their stuff internationally...

Except $16 AUD for Fedex postage is a bit nuts :p

[barefeats]

I can report that I have been able to get three displays to work reliably on all models of Mac Pro from 2006-2010 with both the 5770 and 5870.

Sometimes when I booted up, however, only one display was lit. But when I would pull out one of the Mini Display Port cables, then two would light up. Plug it back in and now three were lit. So there is still some "ooga booga" to do with multi-display support.

Here is my setup:
one 30" Cinema on the DVI port,
one 23" Cinema ($99 dual-link DVI to MDP adapter) on the first MDP,
and one 24" LED Cinema direct to the second MDP.

[jenzjen]

To ANYONE who has had this issue other than myself and GhostKiller, THERE IS A SOLUTION!!!! GhostKiller, your solution to use apple's DL-converter to MDP is a good but expensive solution. I want to thank wally21 for silently solving our problem. IT IS IN FACT THE MONOPRICE CABLES!!!!!! I purchased the circuit assembly 3 meter cables and I have restarted my computer 4 times now, put it to sleep, woke it back up, unplugged it, let it sit, turned it back on, etc... AND FLAWLESS! Just like it is supposed to! I am confirming that the the MONOPRICE CABLES LOSE THE LINK BETWEEN THE 5870 and the DELL U2711's. The Circuit Assembly cables DO NOT. I'm SO GLAD! No my poor computer can get some sleep in it's brand new home for the first time... WITHOUT GOING BLIND WHEN WAKING UP! :cool:

I don't know much about electronics, so I'm hoping someone that does can chime in as to why my setup (Hex / 5870 / 3 Dell U2410s) works with those Monoprice cables? Could the UXX11's from Dell be more sensitive to signal vs the UXX10s?

2 of my monitors are connected via Monoprice MDP/DP cables and the 3rd via vanilla dual link DVI cable.

[akacaj]

I also had the same issue with the Monoprice MDP to DP. New hex core with ATI 5870 card connected to a Dell 2408WFP monitor. I got no signal at all even with a single monitor. Almost cried after waiting for so long to receive my mac only to find out it was DOA. Luckily this monitor has an abundant number of ports so when I tried a DVI cable it worked.

Glad that its just the cable and not my video card. or is it? I used that same cable for over a year with my 17" Mac Book Pro with no problems.

[Gh0stKiller]

I also had the same issue with the Monoprice MDP to DP. New hex core with ATI 5870 card connected to a Dell 2408WFP monitor. I got no signal at all even with a single monitor. Almost cried after waiting for so long to receive my mac only to find out it was DOA. Luckily this monitor has an abundant number of ports so when I tried a DVI cable it worked.

Glad that its just the cable and not my video card. or is it? I used that same cable for over a year with my 17" Mac Book Pro with no problems.

I contacted Monpoprice support about the issue and this was the response I received.

It may be that our cables are not active cables so the the display port connector doesn’t have the chip in it. Since these cables are passive the monitors may not have adaquit power pushed to them to bring them out of hibernate or powersaver mode. Usually the way to remedy this is to just push the power button.

I can confirm that hitting the power button does nothing, but this explanation does kind of make sense to me. Unfortunately, I can't find anything on the Circuit Assembly site that describes their cables as active cables, but maybe they are.

It also makes jenzjen's working 2410s seem even more odd. Maybe that particular model doesn't require as much power?

[JDoggery]

I am having issues using multiple monitors, one via the DVI port and the other 2 with Apple Mini Display Port to DVI adapters (MB570Z/A) with DVI cables. Any ideas? Do I need the Dual Link adapters? I was originally considering using MDP to Display Port, but heard there were issues.

[mjsmke]

Why not have both conected via DVI leads? For the second display use a MDP to DVI adaptor. Thats what i do on a 2009 Mac Pro and ive never had an issue.