iMac Pro T2 Very Lengthy Boot (not with new 2018 MacBook Pro however)

[arjunchawda]

Hi All,

I have the base config iMac Pro, and was wondering if others experienced a very lengthy boot?

My machine sticks on the black screen with apple logo for around 50 seconds before it progresses on to the loading bar (from then onwards it's all very quick).

I've read about a few posts saying this is potentially down to the T2 chip.

In Secure boot, I have no security set.

In terms of peripherals, I just have a couple of USB ports attached (generic drivers), a few SSD's, and a thunderbolt audio interface.

Unplugging ALL of these peripherals makes no difference.

Is anybody else experiences slow boot ups?

(I just received my new MacBook Pro with the T2 chip, and that boots up instantly).

 

[MacRS4]

Unplugging doesn't help...? That's interesting. My iMac Pro can take a while with the hard disks plugged in, but if I remove them then the boot time speeds up significantly. On my Macbook Pro I found that going into Preferences and selecting the boot disk could improve boot-times when I had other drives plugged in too, so perhaps try that?

Have you tried an SMC reset? See here for that: https://support.apple.com/en-gb/HT201295#t2

 

[campyguy]

I own 5 base iMPs, one personal and 4 in my offices. My personal unit has both HS (duh) and Sierra installed, the office units all use HS.

The boot time under HS is a bit slow as you're describing, but the boot time on my personal unit when booting into Mojave (DP4) is a fraction of the time when compared to HS, and it's quite a bit quicker with each new beta. I'm expecting that the new FW from Apple with the next beta will offer a faster boot speed.

 

[mpe]

Yes, it takes ages to boot iMac Pro.

Mine is booting slower than my 1984 Macintosh

 

[AnonMac50]

Mine too, it takes forever to show the progress bar. It's worse when I want to boot into Windows because then I have to press the option key down for like a minute before I can select Windows.

I should add that I have "No Security" set to on.

 

[arjunchawda]

Mine too, it takes forever to show the progress bar. It's worse when I want to boot into Windows because then I have to press the option key down for like a minute before I can select Windows.

I should add that I have "No Security" set to on.

So I played with some configs by clearing the SMC, then unplugging the external HDD attached via USB, and it boots normally now, without a delay.

So it seemed the issue was the external HDD (not the external SSD’s).

Maybe it was taking a while to recognise/mount at pre boot..?