I began commenting on this because I too am looking for a way to speed up rendering within Photoshop, so I don't see how anything that's been said is unproductive. Unproductive is rendering simple letters for over 2 hours on a work PC versus 15-45 minutes at home. I work at a University and have been doing grand format design/printing for over 15 years, and I'm trying to figure out why my $3,000 work PC is getting smoked by an 8 year old home PC that costed one-third that amount so that I can have this problem rectified. I understand the CPU is doing the calculations for the rendering and I never doubted that. But the GPU must be used for render updates on the display at the very least. Maybe that's my GPU utilization spikes on the GeForce cards when rendering and the lack of any utilization on the lower end ATI? Maybe the ATI card can't keep up with displaying what the CPU is calculating? The CPU doing all the rendering doesn't explain away why a top consumer level CPU from 2011 is getting smoked by a new, faster CPU. There are no settings different on one machine than the other. I see the ATI card choke and spit when using liquify or vanishing point, painting complex layer masks, using most any complex brush, working with RAW files, and numerous other times. ... View more

Three year old confirmation isn't really confirmation. It's also hard to explain away the photo and video proof I have of both GeForce GPU's ramping up ONLY after beginning a render with nothing else running. They may not be pegged at 100% utilization, but they jump from 0% to very measurable usage. The Radeon card in PC1 does nothing as far as utilization is concerned. If it were only CPU's doing all the work, the i7 6700 in PC1 should be at least 25% faster than the i7 2600k in PC2, but it's 75% slower in spite of being multiple generations newer, using DDR4 Memory over DDR3 and PCIe 3.0 over PCIe 2.0. ... View more

I have watched the CPU's peg to 100% utilization with Resource Monitor, but I don't believe that the GPU is doing nothing. I've performed monitoring with EVGA Precision and a few other monitoring apps and I've seen my GPU's usage spike to roughly 35% utilization during rendering with nothing else running. All 3 PC's have recent, clean installs of Windows 10 Pro. There is no other reason that I can come up with to rationalize why PC1 is x4 slower than PC2, when every piece of hardware is at least 2 generations newer in PC1, except for the GPU. PC3 is a no-brainer having twice as many cores & a faster GPU. In case storage performance comes up, PC1 has a NVMe SSD, PC2 has a 2.5" SSD from 2011, and PC3 is NVMe SSD as well and I'm not using a scratch disc with any of them. ... View more

If rendering is only handled by the CPU vs the GPU, maybe you can explain this. I'm having rendering issues on my current work PC and have performed the exact same rendering on 3 different PC's. PC-1 has i7 6700 with 64GB RAM and Radeon R7 350X GPU. PC-2 Has i7 2600k, 16GB RAM & GTX 1050. PC-3 has Ryzen 7 1700X, 16BG RAM and GTX 1070. PC-1 took 2 hours and 42 minutes to render. PC-2 took 45 minutes to render. PC-3 took 15 minutes to render. If the CPU handles the renders, why does PC-1 take nearly 4x as long to render when the CPU is 4½ years newer? ... View more