I have been enjoying my 3970x and the Zenith II Extreme quite a bit.
I have 8 sticks of 8GB G.Skill 3600mhz CL15 sticks. (four two pack kits)
I have been trying to dial in what I call 'stock' settings.
Ram about where the XMP profile says.
CPU with default behaviors allowed (some spread spectrum and power saving options off).
Fixed voltages for SoC, CPU, and Ram.
So with that said I am completely stable (Prime 95 w/ AVX used for testing, both high memory and small FFT tested separately):
1.105 volts on vCore + LLC 4
1.39 volts on dram AB and CD
1.15 volts on SoC + LLC 3
My Stock Bios Settings:
One quirk I have noticed. My cpu is completely stable (compute and intense memory utilization) @ .9 volts. However! The ancillary components experience what I am calling hiccups. By ancillary I mean, the ethernet ports, the usb ports, and the sata ports. (NVME drives not affected)
With that low of a voltage the SATA ports are sometimes shown, sometimes not during POST. In windows they function fine, but sustained writes have blips of high latency every 2-4 seconds.
Also the usb ports while writing to a USB stick have the same symptoms. They function perfectly fine, but have hiccups in sustained reads/writes.
The ethernet ports also have the same behavior, but it is much more annoying. While playing games for example your ping may be steady at 25ms to the game server, but occasionally blips to 450ms!!!!
After doing a lot of testing I found that I need 1.1 volts on the cpu cores to get rid of those issues, making my idle temperatures 10C hotter at 40 degrees. Under load, not change in the high temps (59C).
The Soc was ok at 1.1 when I only had 6 dimms. When i added in the remaining 2 I needed 1.15 volts to keep my stock settings of 3600mhz CL15.
Other small notes: I am not using the molex connector at the bottom of the board, nor am I using the extra PCIe power connector near the cpu power plugs. I have to order new power cables to reach these locations for my build. So if this adds more stability at lower voltages I would not know at the moment.
Did some quick overclocking this evening: