xt2 wrote:
Sounds a bit strange for your hardware "karno." I also use an iMac, 4 GHz Intel Core i7, 64 GB 1867 MHz DDR3, & AMD Radeon R9 M395 2048 MB on the Video Card. My machine should be slower than yours, but it is not apparently. It races through my photo management, and post duties. I would make an appointment, and take it into your Apple Store for them to take a look at it. I have had good success with this formula in the past with all things Apple. Good luck!
Many thanks for your input, looks like that’s what I will be doing, Apple did a online diagnostic and said everything was fine.