2009 Mac Pro 5,1 Odd Power Problem

[mastanhope]

So... nobody in my normal circle has been able to figure out what is ailing my ancient Mac Pro, so allow me to pick your brains!

I have a 4,1 > 5,1 Upgraded Mac Pro that I use as my daily driver. Works fine, no issues in general except one pesky power issue.

Ever since upgrading to Sequoia, if I walk away from my Pro without logging off, it will do a HARD shutdown. It shuts down so hard that I can't even turn it on with the power button, I have to physically unplug the machine, and plug it back in and then it will come back on with no issues.

As long as I am using the computer, doesn't matter what I am doing, it works fine. No issues at all. I can sit in front of it all day and do whatever I want, it will not shut down or do anything out of the ordinary. If I log out of the computer back to a login prompt, it will never power off, and will run happily until its told to sleep or power off by me. It only happens when I am logged in and the computer is sitting idle. If I leave a Youtube video playing in the background, it will not power off. It is the oddest behavior I have ever witnessed on a computer of any kind.

I posted specs of my machine, I can give more information if needed, im just stumped. This issue only started once I installed Sequoia on the machine. I ran Big Sur before this with no issues whatsoever. The machine specs haven't changed much except I did install a dual processor tray and more RAM in the machine, but again, I did that under Big Sur and no issues with it for months until I upgraded to Sequoia.

Michael

 

[phunguss]

Since you say if you leave a youtube playing it will not crash, I am guessing it has something to do with one of the sleep states of the CPU. I don't know the underlying issue or change that happened in Sequoia. My daily driver is an iMac12,2 and I have no issues except sleep. This is because I replaced the CPU with a Xeon that does not support sleep. If it sleeps, it crashes. So, I let it run 24/7 and just have a hot corner to lock screen (no screen saver, no auto lock, no sleep). I have disabled all sleep. Granted that a MacPro has Xeon processors, and somehow Apple has them support sleep, I don't know if this is the correct rabbit hole to follow. Just a wild guess at this point.

Other reference from Apple forums.
Also, since you are running Sequoia, I assume you are using OCLP or OpenCore. Maybe sleep is misconfigured?

 

[mastanhope]

Running the latest OCLP on here. Sleep works perfectly, amazingly. I can put it to sleep, and it wakes just fine. I have autosleep turned off thinking that was one of the issues, but it still persists.

I turned everything off in terminal:
mastanhope@Christine-2 ~ % sudo pmset autopoweroff 0
Password:
mastanhope@Christine-2 ~ % sudo pmset powernap 0
mastanhope@Christine-2 ~ % sudo pmset standby 0
mastanhope@Christine-2 ~ % sudo pmset proximitywake 0
mastanhope@Christine-2 ~ % sudo pmset tcpkeepalive 0
Warning: This option disables TCP Keep Alive mechanism when sytem is sleeping. This will result in some critical features like 'Find My Mac' not to function properly.

now I will see what happens. If it doesn't shut down, then I know something above is the culprit, and I can just have a script run that disables everything. I'm not worried about power savings as the machine runs 24/7 anyway, I only sleep it when I won't use it for more than a day (which is rare).

 

[mastanhope]

That didn't do the trick either. I locked the screen, and went out for about 2 hours, and the machine was on, later, i locked the screen and it shut down after about 3 minutes. Back to the drawing board...