While working with Lightroom / Photoshop on a new iMac (December 2017), Lightroom/Photoshop crashes and we get diagonal stripes on the screen (see picture). iMac close everything and restart.
Please clarify something in these two sentences.
Do YOU shut down the iMac and restart it, or does the iMac shut down and restart by itself?
after getting the diagonal stripes... The iMac shut down after a few seconds by itself and restart by itself...
This is either a hardware malfunction or a bad video driver.
You need to re-install the most current video driver for your video card/mother board; and if that doesn't help, then you need to run diagnostics on all of your hardware to see if a problem can be found.
Thanks, drivers and software are up to date on iMac. Run the diagnostics, no problems found.
Check the fans to make sure the CPU is not overheating