Can't Get Startup Manager/Boot Screen to Load

[corpsed]

I just got a new 27" iMac a couple days ago and did a fresh Windows 10 partition install via Bootcamp.

Everything is fine, except I can't get the Startup Manager to load when I do a restart and hold down the OPTION Key.

If I used the Startup Disk program and select the Bootcamp partition and restart, the Startup Manager loads fine. If I hold down OPTION when I restart in the Windows environment, the Startup Manager loads fine.

However... If I hold down OPTION and restart in MacOS Sierra, then the computer simply ignores me and restarts to MacOS Sierra.

I have tried three different keyboards (Magic Keyboard, Corsair K70 USB, another random Bluetooth keyboard)... None of them will load the Startup Manager when I restart MacOS and hold down the option/alt key.

There doesn't seem to be an issue with my Bootcamp install since I can restart via the Startup Disk utility, but that's super inconvenient. Anyone else had this problem and how can I fix it?

 

[Fishrrman]

Could the key mapping on the Corsair keyboard have the option key behaving differently?

 

[corpsed]

No, I've tested the option key several times. It's definitely mapped to the Windows Key. I even tried remapping it to the ALT key just in case.

I've also used the magic keyboard that came with the iMac, so it's definitely not the keyboard's fault. Parallels works fine. Using the Startup Disk program works fine. But if I shut down or restart in Mac OS Sierra and hold the Option/Windows key, it does not bring me to the Startup manager no matter what keyboard I use. I can't figure out what's going on.

 

[corpsed]

Bump in case anyone knows a solution... More than a month now and still can't get boot selection to load with any keyboard... wired or wireless. Switching to Bootcamp and back is a major pain without it.

 

[SaSaSushi]

Without the chime on the new iMac, the timing is trickier. Don't hold down control and restart. Restart and wait for the screen to go completely black. It will go from completely black to a very minimal backlight that is more a dark grey. As soon as it switches to that dark grey, press and hold control.

The switch to the dark grey screen is the beginning of the POST sequence and the moment of the former chime.

 

[corpsed]

Without the chime on the new iMac, the timing is trickier. Don't hold down control and restart. Restart and wait for the screen to go completely black. It will go from completely black to a very minimal backlight that is more a dark grey. As soon as it switches to that dark grey, press and hold control.

The switch to the dark grey screen is the beginning of the POST sequence and the moment of the former chime.

Thanks so much! That is exactly what the problem was... With the lack of chime, I was either holding the button down too early or a little too late. The new iMac boots so fast that there is literally like a half second delay in which you can hold the button down to get the startup menu to appear. If you start holding the button down while the screen is still black, it doesn't work, and if you hold the button down a few milliseconds after the backlit activates, you are too late!

There is super small window of time in which holding the button down works now right after the screen kicks in. They really shouldn't have gotten rid of the chime.

Thanks so much for your help!

 

[SaSaSushi]

I'm glad to hear it worked.

Yeah, I really miss the chime. At the very least, Apple should have left it as a user-configurable option.