How to run Catalina on a 2010 iMac

[lbe]

I have a 2010 iMac running high Sierra and HS is the latest version for this iMac.
As I understand there are ways to make it capable of running Catalina.
How can I do this?

Is it recommended and safe to upgrade and will it run slow on Catalina?

 

[Nguyen Duc Hieu]

1. Replace the original GPU with a metal compatible GPU.
2011 iMac Graphics Card Upgrade | MacRumors Forums

2. Install Catalina with dosdude1 patch.
macOS Catalina Patcher (dosdude1.com)
Notice: Doing 2 without 1. first will result in sluggish performance due to the unsupported stock GPU.
For 2. when creating USB installer, must turn-off auto legacy patching, and de-select legacy VGA package when running post-installation patch.

 

[Fishrrman]

My advice:
Forget Catalina. If you're still using any 32 bit software, it WILL NOT RUN under Catalina.

You could try Mojave first. 32 bit software still runs fine.

If you want to experiment anyway, I would suggest that you get an EXTERNAL USB3 drive (I realize the 2010 has only USB2).
Install Catalina or Mojave ONTO THE EXTERNAL DRIVE.
Try booting and running that way, to see what it's like BEFORE you "commit yourself".
It won't be fast, but it will run...