MP 1,1-5,1 Mac Pro 5.1 Mojave Reboot by itself

[MurdockMan]

Mojave installed with RX580

Reboot randomly after losing screens; sometimes freezes to.

PRAM and SMC reset but nothing have changed.

Sometimes after losing image this "bastard" reboot by himself after a minute or two, but the strange procedure for me is two to four reboot’s in a row, another after another with me doing nothing, and more strange is the system turn off like you turn off the power and after 5 seconds it turn on.

Not all the reboot’s give log´s… put some images to catch the flow of the system.

Not having much time to install opencore after the first attempt failure… follow all the procedures but it stays only in the USB pen.



Thank's for your time... i love this machines

 

[tsialex]

Did you inspect the CPU tray northbridge heatsink push pins?

 

[MurdockMan]

No but a speed inspect because i need to buy the 3mm wrench it seems ok... and changed the battery that was pretty low on voltage... saw a strange fluid in the back of the board near the heatsink... some picture.

The thermal conductor is melting?? Normal?
Always clean the dust year-on-year!!! From 2009 to this 2025!!!

😉

 

[tsialex]

You need to clean it with IPA (sometimes paint thinner is more effective), the oiliy residue + dust are electrically conductive and shorts the PCB.

 

[MurdockMan]

Suspected that was... next step change the thermal?

 

[tsialex]

Suspected that was... next step change the thermal?

Complete maintenance, this is the best thread about cleaning the CPU tray:

https://forums.macrumors.com/threads/mac-pro-mid-2012-no-video-and-a-very-weird-mainboard-processor-board-issue.2315610/page-2?post=30510502#post-30510502

There is a thread about replacing the power plane thermal pads, with what/where to buy, but I don't have it bookmarked.

 

[MurdockMan]

Nice!

I will report the fix!

Thank's

 

[MurdockMan]

Better, stopped the reboot process from times to times, but tomorrow will correct the mess with cotton left behind

The thermal is soft, when touched it's like stick gum... do you advise to change it?