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dickiedunn

macrumors regular
Original poster
Jun 7, 2019
120
2
Hello All,

I made the mistake of installing the recent security update for Mojave and my cMP 5,1 will not boot. I hear the chime and it just keeps cycling.

I tried shutting it off, and resetting the NVRAM (opt cmd P+R keys) for a cycle of 3 chimes, but I still have a blank screen.

I’m running the latest version of Mojave and my boot drive is a Samsung 970 EVO NVME/Kryo PCIe card, which had been running fine.
Also have the Radeon RX580
 
how long have you waiting?
it takes 45 minutes on some computers to finish
and all this time you will see a black screen

if you do a hardreset before you crash your system
 
Thanks for your response. I didn’t wait that long, maybe 10 minutes. But now it chimes, fans spin up, chimes again after a few minutes, keeps repeating. Seems like it is in some kind of loop? Is that normal or should I just let it do this for an hour?
 
I have the old original graphics card, I suppose I could also install that to see what is going on on the black screen?

Recovery mode is on the 970 EVO? Command-R on Boot?
 
swapped out the RX580 for the old Radeon 5770 and did an command option Boot. Selected the 970 EVO and all worked. Then shutdown, swapped back in the RX580 just get a black screen. At least it’s no longer cycling. Any thoughts?
 
Ok, issue resolved. Thanks again got your help. For anyone having a similar issue in the future, here is what I did:

- swapped out RX580 with old Radeon 5770
- Saw grey screen with international no sign
- Restarted holding Option Key down. Saw my 970 EVO Boot drive, selected it.
- Then had the same problem, so had to go into System Prefs—>Startup Disk, and select 970 EVO as the target drive.
- Restart and all seems to be working.

Phew! That was my first experience with a problem and flying blind without a startup screen. Glad I kept the old card to troubleshoot.

Thanks again for your help.
 
Thanks, yes it does show 10.14.6 (18G4032), but not in the overview tab, I had to go to system report—system software overview. I assume the security update completed properly?
 
Thanks, yes it does show 10.14.6 (18G4032), but not in the overview tab, I had to go to system report—system software overview. I assume the security update completed properly?
You have to click on the "10.14.6" in the About This Mac window in order to see the build version.
 
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Good tip, thanks. I didn't know that. Shows version 10.14.6 (18G4032) so I appear to be up to date.
 
Friendly tip: always wait at least a few weeks before installing any security update for this very reason.
I wait for kind folks like yourself to find the problems...... ;)
 
Ha, even better tip! But seriously, I don't know what I would have done differently, other than just wait patiently for an hour? My cMP seems to hangup when I do a "restart". Shutting down and then powering up manually with the power button seems to work better.
 
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