Ryzen 1700 + Extreme LLC OK?

[Dangerous_Dave]

I'm trying to get 3.9GHz out of my Ryzen 1700 so I don't feel like I lost the silicone lottery (again). I'm using an ASUS Prime B350 Plus motherboard, and have set a voltage offset of +0.2V. Using HWInfo, I found that the VCCDR setting is quite a long way from the SVI TFN vcore reading, especially when under load (something like 1.41 VCCDR, 1.385 SVI TFN low load and 1.355 SVI TFN Prime95), and that the CPU was crashing on Prime95 after about 10-15 minutes. The only way to get the SVI TFN reading on high load to approach the reading on low load was to set LLC to Extreme, which then gives ~1.38V Prime95, and the system is stable for over an hour. I haven't checked VCCDR with this setting but it's probably about 1.43V.

I've heard the Extreme LLC setting is generally for LN2 and usually overvolts the CPU significantly under load, but that's not what I'm finding here - in fact it's still just below the low load voltage on HWInfo. Am I reading this situation wrong? Should I be worried about longevity with the settings I'm using here?

 

[Dangerous_Dave]

When there's no load at all the CPU is downclocking to a 15x multiplier and running a much lower voltage around 1.1V I think. I've not really monitored it under a variable load though.