That sounds like a problem with your video card driver - update it from the GPU maker's website.
The driver is up to date. However you didn't answer my question: how can I revert back to 14.1 where I didn't have these issues?
As far as I know the is no way to blackout updates. You may be able to re-install Photoshop CC on top of itself if you have the downloaded the Photoshop CC stand alone installer. That will back level you to the first version. Once you back there use menu help Updates. This will check for updates. If Update 14.1.2 is there your in luck you can uncheck 14.2 update and install all the others. However 14.1.2 may be removed and rolled into 14.2
Adobe releases code without through testing for example a bug was introduced into smart Smart object support and some user interfaces went missing with update 14.2. Adobe need to address to problem of not being able to blackout out bad updates.
Mark, have you investigated the alternate settings available in your Performance preferences panel?
For example, under [Advanced Settings...] there is a Drawing Mode setting. It might be that your particular display driver would rather have Photoshop use one of the lesser settings there. Make SURE to quit/close and restart Photoshop after making a change to a setting in that panel.
Also, you say "the driver is up to date". As there are several ways to do so, it would be good to confirm that you've specifically gotten the latest driver release the manufacturer has released on their own site, not from Microsoft.
Thanks to all for your responses. Changing the Drawing Mode from "Advanced" to "Normal" seems to have done the trick. I tried changing this before, but forgot to close and restart PS before testing it, so it didn't seem to make any difference. It does make you wonder though. It's a pretty high-end graphics card and I've always had it set at "Advanced" before with no issues. Oh, well. Thanks, again.
Glad that helped.
Could be a specific issue with your current driver version. You should probably report it to nVidia or ATI or whomever makes it. And remember to try Advanced mode again when they release their next version.
Well, I was experiencing the same issue.
I rushed to Preferences and found out in Scratch disks I had none checked!
I have checked the boot disk (or any other) and now it works as usual.