Strange flickering on startup on GIGABYTE GA-Z270X-Designare with Mojave 10.14.6

[BillieJo]

Hi all.
It's been a while since I've posted. I know things here are way beyond 2019, the was last time I was building.
My 2019 build which has been working flawlessly... thanks to @UtterDisbelief, @pastrychef, @Edhawk and others has developed a strange issue of sorts.
Just recently my startup sequence has changed not allowing me to get to the boot loader or bios screen.
Now I can't change hardrives in the boot sequence. I have to wait until the machine starts and then go into sys prefs and pick a new startup disc.
And obviously when I shut down the machine reverts back to my start up disc set in the bios when I start up again.
Sleep works perfectly and I can leave the machine on for weeks without problems but shutting everything down from time to time is necessary.

Nothing I do at the beginning or during the start up sequence allows me to get to either screen.
Please excuse me if I'm using the wrong terms. Although I have built 3 machines over the years I'm terrible with taking notes.

I honestly don't know how to fix this. Or if I should as after the boot sequence finishes the machine works fine?
I was going to attach 2 videos. One of the start up sequence and one of the shut down but I can't seem to do that either.
I'm feeling defeated for the moment.

Any thoughts would be appreciated.
Happy holidays to everyone.

 

[UtterDisbelief]

Hi all.
It's been a while since I've posted. I know things here are way beyond 2019, the was last time I was building.
My 2019 build which has been working flawlessly... thanks to @UtterDisbelief, @pastrychef, @Edhawk and others has developed a strange issue of sorts.
Just recently my startup sequence has changed not allowing me to get to the boot loader or bios screen.
Now I can't change hardrives in the boot sequence. I have to wait until the machine starts and then go into sys prefs and pick a new startup disc.
And obviously when I shut down the machine reverts back to my start up disc set in the bios when I start up again.
Sleep works perfectly and I can leave the machine on for weeks without problems but shutting everything down from time to time is necessary.

Nothing I do at the beginning or during the start up sequence allows me to get to either screen.
Please excuse me if I'm using the wrong terms. Although I have built 3 machines over the years I'm terrible with taking notes.

I honestly don't know how to fix this. Or if I should as after the boot sequence finishes the machine works fine?
I was going to attach 2 videos. One of the start up sequence and one of the shut down but I can't seem to do that either.
I'm feeling defeated for the moment.

Any thoughts would be appreciated.
Happy holidays to everyone.

Glad things have been working ... So far!

My first thought when you mentioned BIOS settings is that perhaps the motherboard battery needs changing?

Worth checking?

 

[BillieJo]

Glad things have been working ... So far!

My first thought when you mentioned BIOS settings is that perhaps the motherboard battery needs changing?

Worth checking?

Hi there.
Thank you for replying so quickly.
I can have a look. I think the battery is under a pcie card or two.
I'll open it up and see if I can get it out.
Will I lose all the PRAM settings when I do that?

 

[UtterDisbelief]

Will I lose all the PRAM settings when I do that?

Yes, basically, BUT remember it is not a real Mac, where PRAM is a thing. PCs might call it NVRAM so, as long as your config.plist is working okay, they will get re-inserted on next boot.

All you have to do is re-check your BIOS settings.

 

[BillieJo]

Yes, basically, BUT remember it is not a real Mac, where PRAM is a thing. PCs might call it NVRAM so, as long as your config.plist is working okay, they will get re-inserted on next boot.

All you have to do is re-check your BIOS settings.

Copy that.
Fingers crossed.

 

[pastrychef]

Hi all.
It's been a while since I've posted. I know things here are way beyond 2019, the was last time I was building.
My 2019 build which has been working flawlessly... thanks to @UtterDisbelief, @pastrychef, @Edhawk and others has developed a strange issue of sorts.
Just recently my startup sequence has changed not allowing me to get to the boot loader or bios screen.
Now I can't change hardrives in the boot sequence. I have to wait until the machine starts and then go into sys prefs and pick a new startup disc.
And obviously when I shut down the machine reverts back to my start up disc set in the bios when I start up again.
Sleep works perfectly and I can leave the machine on for weeks without problems but shutting everything down from time to time is necessary.

Nothing I do at the beginning or during the start up sequence allows me to get to either screen.
Please excuse me if I'm using the wrong terms. Although I have built 3 machines over the years I'm terrible with taking notes.

I honestly don't know how to fix this. Or if I should as after the boot sequence finishes the machine works fine?
I was going to attach 2 videos. One of the start up sequence and one of the shut down but I can't seem to do that either.
I'm feeling defeated for the moment.

Any thoughts would be appreciated.
Happy holidays to everyone.

I encountered this once...

The only way I was able to get back to the BIOS was by pulling the SSD which contained OpenCore. Once I got to BIOS, I reset to default and redid the settings.

 

[BillieJo]

I encountered this once...

The only way I was able to get back to the BIOS was by pulling the SSD which contained OpenCore. Once I got to BIOS, I reset to default and redid the settings.

Hi @pastrychef. I was hoping that wouldn't be needed but the thought had crossed my mind.
The SSD which is the start up disc is an M2 type on the motherboard. That along with 4 other SSDs all have the OSX on them so I can use any of them to run the machine.
Getting to that M2 SSD is probably just as hard as replacing the battery.
They're both under the graphics card and another pcei card.
Once I'm finished with the audio work I'm doing currently, I'm going to strip the machine of all the SSDs, change the battery and try to boot from the USB. You mentioned OpenCore. This machine is running on CLOVER.
I'm now wondering if the components I used in 2019 will let me move to an OpenCore build?
I need to stay on Mojave as far as I know. This machine was built strictly for Pro Tools. I need to read up on other current builds to see what others are using...

I'll keep you posted as I brave the waters.

 

[pastrychef]

Hi @pastrychef. I was hoping that wouldn't be needed but the thought had crossed my mind.
The SSD which is the start up disc is an M2 type on the motherboard. That along with 4 other SSDs all have the OSX on them so I can use any of them to run the machine.
Getting to that M2 SSD is probably just as hard as replacing the battery.
They're both under the graphics card and another pcei card.
Once I'm finished with the audio work I'm doing currently, I'm going to strip the machine of all the SSDs, change the battery and try to boot from the USB. You mentioned OpenCore. This machine is running on CLOVER.
I'm now wondering if the components I used in 2019 will let me move to an OpenCore build?
I need to stay on Mojave as far as I know. This machine was built strictly for Pro Tools. I need to read up on other current builds to see what others are using...

I'll keep you posted as I brave the waters.

There's no reason why OpenCore won't work.