I have a late 2012, 27" iMac with graphics issues, BUT...

I have a late 2012 27" iMac with graphics issues.

(27-inch, Late 2012)

10.15.5

NVIDIA GeForce GTX 680MX 2 GB

3.4 GHz Quad-Core Intel Core i7

Some apps just don't seem to work and others go all screwy graphics wise such as safari, maps and firefox and sometimes the screen just goes haywire flashing, geometric flickering etc.

Some months ago I posted this and was suggested that learned that graphics "card" was in fact part of the processor so a replacement unlikely.

BUT... no graphics issues when booted from an external with older system OR booted in SAFE MODE but of course many things are disabled there anyway.

Is it logical to assume that even in SAFE more or booted from another drive, the graphics are still governed ** the graphics "card" in the iMac itself?

So then doesn't the lack of GRAPHICS MAYHEM in those situations mean that it ISN'T the graphics card but something else?

I'd rather not have to buy a new mac right now.

Oh and some one suggested the fans might be clogged. I tried a vacuum on them and that doesnt appear to be an issue but how the heck to you clean inside one of these iMacs anyway?

Thanks for any help.

Jeff