I'm having a lot of problems with the app hanging and showing a beach ball, even for the easiest tasks. I already tried the change the video settings and the allocated memory but it doesn't help. My Photoshop STUDENT is also having this issue and he has 20gb of RAM.
Have you installed the Photoshop CC 2015.1.1 update?
What OS version are you using?
Most of the hangs we've seen have been due to third party plugins or extension panels, utility programs (like antivirus or firewalls) and external applications (Chrome, for one).
A few people have also had trouble when they had corrupt fonts or OS font caches on their system (see https://helpx.adobe.com/photoshop/kb/... )