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Question: Problem with ports and mac pro 2013 turning off randomly

Hi all,

Just a quick one to see if anyone has any advice on this or has experience anything similar. I'm on a late 2013 Mac pro (3.5 6 core) Cylinder running 10.13.3.

A few weeks ago my mac started displaying some sister behaviours. Crashing if a monitor was unplugged or turned off was the most common. Normally when this happened, after I restarted the machine, it would be so slow that it was basically unusable, like it would take 5 mins for the mouse to move across the screen, keyboard wouldn't work, and sometimes the computer wouldn't recognise the USB ports or monitors. The trouble with this problem is that when it occurs, I can't do any startup commands e.g. starting in safe mode, recovery mode etc, because it doesn't seem to recognise the ports properly, especially the USB. I've tried plugging monitors, keyboard, mouse into different ports and isolating buses but it doesn't make a difference.

Now my computer is also randomly switching off, and sometimes takes about 30 mins of continual restarting to get it to turn on and work normally. It appears to be random when it does work.

I've tried hardware tests, reinstalling operating system, resetting SMC, PRAM etc, and nothing seems to work. I've run a diagnostic which didn't show anything, and have done a disk check which was fine. The RAM is also showing is fine in the system report.

Seems like a hardware problem but I'm not in a work schedule position at the moment to have the computer repaired. Any ideas?


Mac Pro (Late 2013), macOS High Sierra (10.13.3)

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Mar 5, 2018 3:16 PM in response to Smokerz In response to Smokerz

Thanks for your response – yes good point! I normally have 2 x monitors plugged into the thunderbolt ports, a USB external hard drive, and keyboard into the USB, sometimes a thunderbolt RAID and external GPU plugged into the thunderbolt ports. The reason I didn't mention it is because the problem still occurs when there is nothing apart from a single monitor connected, I have tried different monitors, different keyboards, and different power plugs/cords and it doesn't seem to make a difference. Interestingly, I can pretty much guarantee a crash if I have an iphone plugged into the keyboard USB, and then unplug it, the system will freeze almost instantly.

Mar 5, 2018 3:16 PM

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Mar 5, 2018 3:59 PM in response to Lukas Schrank In response to Lukas Schrank

resetting smc and or pram is not going to work if you continually attach externals improperly. My guess is yes you do. for example you are not specific about how you attach those two displays. hopefully they are on separate thunderbolt buses.

External GPU, what would you expect.

Mar 5, 2018 3:59 PM

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Mar 5, 2018 4:09 PM in response to Smokerz In response to Smokerz

Thanks – yeah not sure anymore, as I mentioned the issue happens even when there is only one display and keyboard plugged in. The problem began before I even owned an eGPU and there was no iphone plugged in. The iphone quirk is a new thing...The problem also persists regardless of which port/buses are used – most recently I'm keeping each bus with only one connection.

Mar 5, 2018 4:09 PM

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Question: Problem with ports and mac pro 2013 turning off randomly