2017 iMac won’t start after ram upgrade. Yikes 😳

[tps7c]

Hi everyone! So today I tried to upgrade my 2017 27” iMac 5K from the original 16 MB to 64 MB of RAM. The RAM was from Crucial, and is the correct RAM for this model. When I installed the ram, it started up but brought up an error screen, and then a second error screen, which I will post screen grabs below. The first message says that my Mac is restarting because of a problem, and the second one was just a link to Mac start up support. I removed the new RAM and put in the original apple ram, and even that won’t start up now. It brings up the same identical messages. I tried clearing the PRAM, and still nothing works. Does anyone have any ideas on what I could try before I have to bring this into a store to be looked at? I’m just really surprised that even the original ram is no longer working. Any help would be greatly appreciated, thanks!

 

[Nguyen Duc Hieu]

Try PRAM reset first.

Just to be sure, did you swap your RAM when the iMac was still connected to the power socket?

 

[Fishrrman]

First step is to TAKE OUT the new RAM, and put the factory RAM back where it was.

Will it boot up then?

If so...

Try taking out the factory RAM, and using ONLY the Crucial RAM.

Does it boot now?

 

[Lasermoon]

Take the ram sticks out and clean the gold pins with alcohol using a cotton bud on both sides, then blow compressed air in the ram slots.
Then try again.

 

[rpmurray]

Usually that second screenshot means that your startup disk contains a Mac operating system, but it's not a macOS that your Mac can use. Have you tried using recovery mode?

Start up your Intel-based Mac in macOS Recovery​

1. Restart your Mac.
2. Immediately press and hold one of the following key combinations until you see the startup screen:
   • Command-R: Start up from the built-in macOS Recovery System. Use this key combination to reinstall the latest macOS that was installed on your system, or to use the other apps in macOS Recovery.
   • Option-Command-R: Start up from macOS Recovery over the internet. Use this key combination to reinstall macOS and upgrade to the latest version of macOS that’s compatible with your Mac.
   • Option-Shift-Command-R: Start up from macOS Recovery over the internet. Use this key combination to reinstall the version of macOS that came with your Mac or the closest version that’s still available.
3. If you see a lock, enter the password for your Mac.
4. If you have multiple volumes on your disk, select the volume you want to recover, then click Next.
5. If requested, choose an administrator account, click Next, enter the password for the account, then click Continue.
   When the Recovery app appears in the menu bar, you can choose any of the available options in the window or the menu bar.