Using layer FX has a major effect on performance. Relatively light documents become painfully slow when I have fx on a few layers. This forst started when using fx on groups so I avoided that but now seems to be a problem on layers too.
If I rasterize the fx then performance returns but this is no solution.
I thought this may be linked to a 4k monitor but a colleague has the same issue using a regular HD screen.
I am using a high performance Dell Workstation so this shouldn't be an issue.
Apologies - thought it may be a common problem. More info:
Photoshop CC 2014.2.2 (latest build via cloud)
Win 7 Pro 64bit (6.1, Build 7601)
Dell Precision Workstation T3610
BIOS Date: 07/24/14 Ver: A08.00
Xeon CPU E5-1650 @ 3.50Ghz (12 CPUs)
Nvidia Quadro K4000 4095 (current display mode 3840x2160 32bit (29Hz))
SSD HD + 2x HD RAID
Typical canvas size from 1200px - 4000px
I have tried optimizing History & Cache to tall and thin, Big and flat + various custom settings.
Memory usage set to 83%
Use Gfx Processor checked.
Scratch disks set to: Primary D and secondary C (Startup)
*As well as the above description, simply hiding the layers and/or switching off Layer Fx also appears to restore performance.