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warbler

macrumors newbie
Original poster
Apr 22, 2023
24
3
My mid-2010 Mac Pro (5.1) has worked fairly flawlessly until yesterday. I moved to a new apartment about 5 days ago. I hooked up my computer and two monitors. I booted up. Both displays worked perfectly. Leaving the screen saver on, I left for a few hours. When I returned, the right monitor screen was black. I rebooted, still a black screen, however, the monitor showed it's manufacturers logo and the message, "No Signal" before going black, so I determined the monitor and connections were OK. I unplugged the computer for a while, then rebooted. Still, right monitor was black screen.

What could be happening here, and how I can fix it? Diagnosis and remedy, please.

Thank you
 
Could be an issue with any number of things, including the GPU, cable, and/or the actual monitor itself.

Are the two monitors identical (or similar) models? If so, you might want to try swapping the cables, or plugging into a different port on your GPU. I've had it happen on my 5,1 where I just plug the DisplayPort (for example) in, the other monitor will go black, then when I disconnect/reconnect monitor #2, they both show up. I know, it's weird, but that's what I've experienced before.

Also, could you please provide more details about your system, including the OS version and what GPU you're running?
 
Could be an issue with any number of things, including the GPU, cable, and/or the actual monitor itself.

Are the two monitors identical (or similar) models? If so, you might want to try swapping the cables, or plugging into a different port on your GPU. I've had it happen on my 5,1 where I just plug the DisplayPort (for example) in, the other monitor will go black, then when I disconnect/reconnect monitor #2, they both show up. I know, it's weird, but that's what I've experienced before.

Also, could you please provide more details about your system, including the OS version and what GPU you're running?
I thought because I could see the display logo and "No Signal" message, that would indicate the monitor is working OK. The connections are solid. I suppose there could be a faulty cable or connector. I will try swapping the cables and see what happens.

This is not a new setup. I have been running my computer with this same equipment for years.

I am attaching System Preferences information.

Thanks very much. I really appreciate your help.
 
The monitor showed you the manfacture logo really only really means it can show you the manufacture logo. Doesn't imply the other part (e.g. input) of the monitor is working correcly.

Also, this doesn't imply the cable is working correctly.

I understand that your setup works for years. However, since you moved it to a new place. The stability may be gone. Even electronics shouldn't be like that. But the reality is that they do.

In your case, it's so easy to perform swap test. You really should try to swap cables, and swap monitors. So that you can identify the problem is at the graphic card, or at the cable, or at the monitor. Just 3min work, help diagnosis a lot.

Anyway, when you re-connect them to perform swap test, better give the connectors a good blow. Make sure not just some dust blocking the signal.
 
Hide your serial number on the 2 screenshots....;)
Oops. I had no idea that would be a problem. What could happen with exposed serial numbers? Could that allow entry into my computer?
 
The monitor showed you the manfacture logo really only really means it can show you the manufacture logo. Doesn't imply the other part (e.g. input) of the monitor is working correcly.

Also, this doesn't imply the cable is working correctly.

I understand that your setup works for years. However, since you moved it to a new place. The stability may be gone. Even electronics shouldn't be like that. But the reality is that they do.

In your case, it's so easy to perform swap test. You really should try to swap cables, and swap monitors. So that you can identify the problem is at the graphic card, or at the cable, or at the monitor. Just 3min work, help diagnosis a lot.

Anyway, when you re-connect them to perform swap test, better give the connectors a good blow. Make sure not just some dust blocking the signal.
The set up is two VGA output monitors, ASUS (functioning, ViewSonic black screen). The functioning ASUS connecting to a DVI adapter, the black screen ViewSonic connecting to a Mini DisplayPort adapter. I kept the VGA cables attached to each monitor and switched the connections at the DVI adapter and Mini DisplayPort adapters.

The DVI port originally connected to the functioning ASUS, proves those cables and port are functioning.

After switching the cables, the ASAS now connected to the Mini DisplayPort is black screen, and the ViewSonic connected to DVI adapter is functioning.

This proves the DVI adapter and port are functioning, as well as each of the VGA cables.

The problem is isolated down to the Mini DisplayPort adapter and/or port itself.

The Mac Pro has two Mini DisplayPorts. I rebooted with the adapter into the second Mini DisplayPort. That proved black screen, too.

So, I believe I isolated the problem down to either the Mini DisplayPort or the ports themselves. Since I tested each of the two Mini DisplayPorts and neither of them functioned, wouldn't that indicate that it is likely the adapter failed? If the monitor functioned with the second M DP, that would indicate the adapter functions and isolate the problem down to the first M DP. However is not the case.

My guess, likely the Mini DisplayPort adapter, but it could also be the port, if both ports are connected to the graphics card at the same location where it might be failing.

What would be your diagnosis? Should I pick up another Mini DisplayPort to switch it out? Is there a way of bench testing the Mini DisplayPort adapter? What are my next moves?

Thank you
 
Could be an issue with any number of things, including the GPU, cable, and/or the actual monitor itself.

Are the two monitors identical (or similar) models? If so, you might want to try swapping the cables, or plugging into a different port on your GPU. I've had it happen on my 5,1 where I just plug the DisplayPort (for example) in, the other monitor will go black, then when I disconnect/reconnect monitor #2, they both show up. I know, it's weird, but that's what I've experienced before.

Also, could you please provide more details about your system, including the OS version and what GPU you're running?
Hi, I want to let you know that I just posted a detailed reply to h9826790. I hope you can join in on this diagnosis.
 
Oops. I had no idea that would be a problem. What could happen with exposed serial numbers? Could that allow entry into my computer?
Not hacking into your computer.

But think this way, if a Hackintosh maker want a valid serial number to build his Hackintosh. Then he see your post, and “borrow” that serial number.

Later on, Apple server realise two different computers use the same serial number to login the Apple server. The server may block this serial number automatically.

For the Hackintosher, he just change the serial number, then be a happy user again. However, you genuine cMP may be blocked forever.

The set up is two VGA output monitors, ASUS (functioning, ViewSonic black screen). The functioning ASUS connecting to a DVI adapter, the black screen ViewSonic connecting to a Mini DisplayPort adapter. I kept the VGA cables attached to each monitor and switched the connections at the DVI adapter and Mini DisplayPort adapters.

The DVI port originally connected to the functioning ASUS, proves those cables and port are functioning.

After switching the cables, the ASAS now connected to the Mini DisplayPort is black screen, and the ViewSonic connected to DVI adapter is functioning.

This proves the DVI adapter and port are functioning, as well as each of the VGA cables.

The problem is isolated down to the Mini DisplayPort adapter and/or port itself.

The Mac Pro has two Mini DisplayPorts. I rebooted with the adapter into the second Mini DisplayPort. That proved black screen, too.

So, I believe I isolated the problem down to either the Mini DisplayPort or the ports themselves. Since I tested each of the two Mini DisplayPorts and neither of them functioned, wouldn't that indicate that it is likely the adapter failed? If the monitor functioned with the second M DP, that would indicate the adapter functions and isolate the problem down to the first M DP. However is not the case.

My guess, likely the Mini DisplayPort adapter, but it could also be the port, if both ports are connected to the graphics card at the same location where it might be failing.

What would be your diagnosis? Should I pick up another Mini DisplayPort to switch it out? Is there a way of bench testing the Mini DisplayPort adapter? What are my next moves?

Thank you
I bet the adaptor as well. It’s extremely rare that only both mDP failed, but the whole graphic card still working.

Only one port sudden fail is totally possible, but only both mDP fail at the same time. I don’t think so.
 
Not hacking into your computer.

But think this way, if a Hackintosh maker want a valid serial number to build his Hackintosh. Then he see your post, and “borrow” that serial number.

Later on, Apple server realise two different computers use the same serial number to login the Apple server. The server may block this serial number automatically.

For the Hackintosher, he just change the serial number, then be a happy user again. However, you genuine cMP may be blocked forever.
Is there anything I can do at this point to delete those images that reveal my serial number?

I bet the adaptor as well. It’s extremely rare that only both mDP failed, but the whole graphic card still working.

Only one port sudden fail is totally possible, but only both mDP fail at the same time. I don’t think so.

Success!!! I went down to my local Resource/Reuse store where they located numerous used Mini DisplayPorts to VGA. They tested two on a iMac and both tested OK. I bought the one appeared to be a brand new, a Dell adapter for a buck ($1) I am replying now on the monitor that was previously black screen!

Many thanks to you, and the others that helped along the way!
 
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