Skip to main content

Model A1418 / Late 2012 / 2.7 & 2.9 GHz Core i5 or 3.1 GHz Core i7 Processor

212 Questions View all

New Ram and SSD Unusably slow

Block Image

Block Image

I own a repair shop I have a 21.5 inch late 2012 iMac is running so slow it times out installation of OS, and is jumpy during navigation of installation media. New Ram old ram same issue, new SSD old HDD same issue, new thermal paste same issue, any ideas are much appreciated.

Answered! View the answer I have this problem too

Is this a good question?

Score 1
10 Comments

Your system is in CPU Safe Mode, which the SMC logic lowered your systems CPU clocking and the fan is cranked up. Which is why your system is so slow and the jerky!

Restart the system and run the onboard diagnostics pressing the D key. Let us know what you got for errors.

Reference: Mac startup key combinations

by

@danj

Error: 0x8000000000000003, Cannot Load 'EFI/Drivers/TestSupport.efi

Status: 0x00000003

by

@danj Also it is connected to internet via ethernet so it should have connectivity. do I need to have a HDD with an OS installed connected to the Mac for this to work?

by

@gizmowizards - Sorry I got busy this afternoon. Diagnostics does not use your OS.

At this point you'll need to run diagnostics again, this time press the Option key as well as the D key. to get into the Apple server diagnostics. Make sure you have your system wired via Ethernet to the internet. Did you get an error at this point?

by

Show 5 more comments

Add a comment

1 Answer

Chosen Solution

I think the original problem was a bad HDD was causing a similar issue as the lagging and jumpiness, but after I installed the SSD I never reinstalled the LCD I only tested without it, so it seemed like it was the same issue but it was a sensor not plugged in.

Was this answer helpful?

Score 1
Add a comment

Add your answer

Randy Northrup will be eternally grateful.
View Statistics:

Past 24 Hours: 0

Past 7 Days: 0

Past 30 Days: 5

All Time: 186