iMac 27" 820-3481 slow keep crashing

ielectron

Member
Hi everyone,
I have a problem with this iMac model its very slow once I want boot it up from usb with fresh osx tried a few same on all of them. With customer SSD booting up but crashing and restarting.
I've tried a new ssd but didn't get chance to install fresh osx because is not possible
I refresh BIOS no changes
test AHT no errors found
Looks like some temperature sensor but there is no schematic so can't even see where they are.
I tried with disconnected camera no results.
Does anyone had issue like this before ?
thanks for help
 

2informaticos

Administrator
Staff member
Any history available, some "upgrade" attempt?

"I refresh BIOS no changes"
Did you clean ME region?

Can you run Windows, or Linux Live USB?
 

ielectron

Member
I know for sure it was open somewhere else as the glue on the screen has been removed and replaced with some other different one. board looks untouched no liquid damage.
Sorry I meant, reflash BIOS, I do clean ME region
I actually didn't try run a windows live I will try it now to see if works
 

ielectron

Member
just tried run windows from stick and its loading fine and works
but osx installation usb stick want load and osx itself is crashing
what do you think ?
I've replaced EFI IC just in case and load in old bios with clean ME region still same
Here is a video when trying to boot to osx and crashing
its crashing in same moment on progress bar when trying to load in from usb stick
 
Last edited:

2informaticos

Administrator
Staff member
Could be GPU issue also.
This will explain why runs Windows Live, which doesn't load GPU driver.
But is worth to discard ME region first...
 
Top