Having just gone through this, and so that it's easier for others to find the fix, I'll post a reply here.aoktar wrote:It mentioned in standalone topic. it's under investigation.SRCOBB wrote:I think we know this, but I just want to confirm, the AVX issue with older CPUs is still there. C4D will not open at all with 2020.1.3 installed.
I was making the jump from 2019.x to 2020.x for our production machines this week and found that our old MacPro cheese-grater tower render node (ironically our oldest, but fastest machine with 2 x 1080 TIs, SSD, and tons of RAM) could not launch 2020.1.3 Slave or Stand Alone. With some help from Beppe (thanks!), I rolled it back to 2020.1 for the slave, and 2020.1R7 for the masters, and all is well.
I would be nice to have some of the later tweaks and features, but for the current job we are working on, it's really just the OSL displacement on VDBs that is crucial. So for the next few months until this job is done, we'll be sticking to this configuration for all production machines.
Update:
Based on some previous discussions on the forum and more input from Beppe, I switched the old MacPro tower over to Ubuntu 20.4, which doesn't have the AVX issue despite using the same CPUs, so now it can run as a 2020.1.3 render node. Apparently this configuration should run RTX 20xx cards as well, when the time comes for yet another upgrade to this venerable workhorse.
It seems that when rendering PNGs instead of an EXR with the image color profile set to Linear and the Tonemap type set to tonemapped, as I have set in the screenshot, it works as it should without any issue. I guess what I'm saying is it does not work the way it use to for all of the past versions for me. Any ideas on this? 
