Mac OS Ventura 13.5-update BROKE Mac Pro firmware or hardware?

okay4353 wrote:

After updating to Mac OS 13.5 on the 2023 Mac Pro M2 Ultra

the Mac rebooted normal and around 1 min after login it started to turn up the top fan very high (running around 2490 rpm, before it was 500 to 600) ... first there very many processes and optimization running but it did not stop...

Before the update the Mac was almost completely quiet (latest 13.4).

-I bootet Mac OS in Safe Mode - no change

-I reinstalled Mac OS on the existing hard disk - no change

-Even when installation startet, the fan was running so fast (I installed it from the menu, available from booting the machine with the power key holt for a few seconds).

-A completely new installation of Mac OS 13.5 on another SSD - no change

Seems there is a problem with hardware? Maybe the Mac firmware was corrupted with the first 13.5

update? Or it broke a hardware part? The German Apple hotline told me, I should contact a local Apple Service partner, if these previously mentioned options don't help...

Is there another possibility?

If the Mac is hot I would let it cool down before you reboot as normal.

Apple support is here—>

Call Customer Support (800) MY–APPLE (800–692–7753)

or on line https://getsupport.apple.com/

Outside the USA—Contact Apple for support and service by phone

See a list of Apple phone numbers around the world.

Contact Apple for support and service - Apple Support

Make sure to disconnect all external devices in case one of them is causing a problem. If this is a desktop system, then of course you need to connect a display.

Did you try to perform a firmware "Restore"? Unfortunately this requires access to another Mac running macOS 12.4+ (at least last time I checked, the OS requirement for the host keeps increasing). This destroys all data on the internal SSD, resets the firmware & security enclave & pushes a clean copy of macOS onto the internal SSD. Test with the clean install before installing any third party apps and before restoring from a backup since third party apps & restoring from a backup could bring the problem back. For testing we want to know if a pure system still has the problem since this will tell us if this is a hardware issue or an issue with third party software (or a bug with the update).

Revive or restore a Mac with Apple silicon using Apple Configurator - Apple Support

You can try running the Apple Diagnostics to see if any hardware issues are detected.

Give this a try:  How to reset the SMC of your Mac - Apple Support

Be sure to disconnect all peripherals before resetting the SMC. 

Thanks for the update. Glad you've fond the cause and can work around it.

Same with me. All network apps were down (mail, MSTeams, safari...). I unplugged Ethernet and back to normal.

very strange.

thanks for the tip