Photoshop Unusably Slow and causing overheating

[Stapprints]

In the past week photoshop has become unusably slow and causes my computer to get roasting hot and the battery to deplete at 10x the usual rate.  Zooming has a lag measurable in seconds and basic stuff like cloning or even selecting is virtually impossible - I clocked a simple one-layer clone stamp at over 30 seconds from the time it was drawn.  It's actually uncomfortable typing this post at the moment because the keyboard is so hot after trying to do a content aware fill on a single layer document. 

I updated to the latest version in the hope that it would help, but it hasn't.  The computer is unlikely to be the issue as it's a well specced Macbook Pro (2.3 GHz 8-Core Intel Core i9, 32db RAM) with a 1tb SSD that has a lot of free space. No other app causes this to happen to the computer.  I've also previously run massive .psd projects on this machine without it being in any way taxed.  

I've tried the various trouble shooting tips (optimisation, security etc) but nothing has helped.  This is really holding me back from being able to work. 

[josephlavine]

It sounds like a computer issue, but something to try is to uncheck the Graphic Processor in the Preference panel.

warmly/j

[Francesco Della Peruta]

Hi, have you try to follow these suggestions?

https://helpx.adobe.com/photoshop/kb/photoshop-slow-lags.html

[J453]

Let's make sure we're in a default state and there are no stale setting somewhere:
Restore your preferences using this manual method:
https://helpx.adobe.com/photoshop/using/preferences.html#Manually
Does it work correctly?
If that doesn't solve it, you can quit Photoshop and put the Settings folder back.
If it does solve the problem, I would like to get the folder of settings to try and figure out what is bad with them.

[Stapprints]

Thanks for the suggestions.  I tried them but didn't notice a difference. Decided to delete all Adobe products and preferences off the computer and reinstall and that has improved things.  Definitely a bit slower than it was a few weeks ago (on par with our spare 2012 MBpro which is nowhere near as well specced), but usable again.  I'll see how it holds up over the next few jobs. 

Re: The computer - I did full diagnostics on the machine and nothing seems out of order. It definitely appeared to be a photoshop-specific problem - no other apps are affected (Lightroom, Logic Pro, Final Cut, Reason all worked flawlessly without sending my computer into a frenzy).