I have the same CPU with 128GB ECC memory installed and I have similar problems on both Windows and Ubuntu OSes, for example in windows 10 if I load Folding@home, BOINC with Rosetta@home project and start some VirtualBox machine with Windows XP that uses 16 cores, then system becomes non-responsive and everything lagging a lot, so every move takes ages. If I do similar tasks in Ubuntu - the system GUI, mouse rendering is much better overall, but virtualBOX machine lagging a lot and if you try to load some youtube video on firefox on ubuntu system at the same time, then you will get some stuttering in video and sound also.
On Windows I have running RealityCapture software that causing a lot of stuttering when I trying to reconstruct the model with large amount of files and the reconstruction ends with error, If I use Intel PC with same amount of memory and settings in windows, then I can successfully complete the reconstruction. If I disable SMP for AMD in BIOS then I can also complete the project on AMD.
Can anyone comment this?