Random 'sleep' mode in LR Classic while active

[buzzbeat1]

I'm on a mid 2013 'vintage' (Apple's term) iMac with 32 GB RAM, and in the last week it has randomly started going to 'sleep' while I'm actively working on a photo. When I click on the keyboard it does re-activate and it seems to keep running underneath. For example, I was exporting a batch of photos and it appeared to keep working while the screen was dark. It did however turn off Amazon music that was playing. Unfortunately, it's become nearly impossible to work on photos as it's going off every couple of minutes (sometimes more frequently).

Other than installing Topaz a few weeks back I'd made no changes to the system. Topaz software doesn't run until activated and in all cases it was not loaded when these incidents occurred.

To troubleshoot so far ...

1.) I rebooted

2.) Tried in 'safe' mode

3.) Installed the latest version of LR (the new masking is awesome BTW)

4.) Installed the latest Mac OS

5.) Ensured I have 300GB available on both my main HD (1TB) as well as the destination folder (4TB)

6.) Run Photoshop with LR off w/o any issues to ensure it's not a general Adobe issue

7.) Run numerous other apps w/o issues to isolate that it does seem to be LR specific

Other than the obvious answer of get a non-vintage machine, which I am planning to do later next year, has anyone run into this problem and found a solution? Google and YT searches aren't helping 😞

Thank you in advance for your suggestions.

[GoldingD]

This is unlikely to be an issue with any program. This would be an issue with your MACOS power settings, drives going into power savings, or the computer going into power saving, and if s Laptop, on battery, going into low power operation upon low battery state.

[buzzbeat1]

Thanks for your reply. My power saving is set for 90 mins and I would think that the power settings would effect software universally vs. just LR. The blackouts are also happening at random times vs. a consistent pattern e.g. every 5 mins. For clarification, it's an iMac vs. a laptop.

[buzzbeat1]

I'm knocking wood as I type this but, the Adobe support person may have found a fix ... "Please try turning off the GPU option from Lightroom's preferences. Go to Lightroom > Preferences > Performance tab > Uncheck "Use Graphics Processor" > Restart Lightroom."

In my case, I turned it off (wasn't a check box) and so far, so good. No black screens with 30 minutes of continuous editing.