Hi-
PC is an HP Pavilion dv7, with i7 processor, 16 GB of RAM (max for the machine), c-drive has 600 GB free, external USB3 drive (f) has 900 GB free. Windows 7, sp1 with all latest patches.
Photoshop CC 2014 is installed along with Lightroom 5.4. Photos are stored on F-drive. LR/PS runs off of C, of course, with all cache files located there.
All apps on the machine seem to run ok. My normal workflow with LR/PS is to do as much in LR as I can, but more detailed edits on a photo require PS- so I do a CTRL-E. PS pops open and I start to work on the file. Everything is good for awhile.
Then suddenly, PS seems to freeze. If I continue working, it does not respond for 1-10 seconds, then all of a sudden, everything I did in those 10 seconds happens all at once. So my movements seem to be "cached" and then they happen in quick succession. Even something as simple as renaming a layer- I can type the name and I see nothing on screen, then bang- the new name appears. Then it will work fine again. A minute or so later, I'll get a "herky jerky" response again- the mouse will even seem to jump across the screen rather than move smoothly.
It's weird. No other apps on the machine exhibit this problem.
I've turned anti-virus and anti-malware protection on and off. I've played with the Photoshop performance settings over and over- same problem occurs.
My files are generally from a Nikon D800 camera- 36 Mpixel images with Lightroom adjustments. I've had the camera for a couple of years and never had this problem with images before, and my workflow has not changed.
If someone has answer- great. But I'll be happy with a direction to start troubleshooting this. It's driving me nuts. My workflow slows to a crawl at times and I have a lot of photos that need editing!
Any help appreciated.