@DrMrLordX
I was just wondering how the 3900x performed with ECO-mode selected and all other CPU tweaks set to Auto or Normal or Default.
Fair enough. Let me try poking around a bit . . . one thing I can tell you is that setting Eco Mode with Ryzen Master makes the PC want to reboot itself. Hmmm! Odd.
edit: okay, did some quick testing. I found Eco Mode under the AMD Overclocking options in the UEFI of this x570 Aorus Master motherboard. First test is with LLC 0/LLC Off, no voltage offsets, and Eco Mode activated. Note that I left my memory OC in place which may or may not lead to excessive amounts of the package power being committed to the I/O die during MT testing. But really, running DDR4-2133 is ridiculous, and I don't feel like dialing in a completely different memOC for the test.
Single-threaded testing was conducted with SuperPi 1.5 mod XS. It's an SSE2 benchmark, and it is very good for isolating single-core boost behavior. Result: ~9.02 seconds, which is consistent with the performance that I get running the same config without Eco Mode. The weird thing is that I saw the highest temps I've ever seen in a single-core benchmark! The chip showed temps in excess of 55C. CPU-z reported really high voltages, too - 1.48v and (slightly) higher. I observed the same behavior in ST Cinebench R20.
Then I went for an MT test: CBR20 MT. Temps were stupidly low (44C-ish) and Ryzen Master reported the chip hitting a cap of 87W. Result was ~6550, which is quite a bit lower than the ~7200-7250 I usually get running this config without Eco Mode.
Pondering this for a bit, I decided to slap on negative voltage offset to see if I could force the chip to clock higher. This works without Eco Mode in MT scenarios, so would it work with Eco Mode?
Running SuperPi 1.5 mod XS again, the -.1v offset drove voltage down to 1.392v and produced a score of 9.045s which is very close to what I had without the offset. Again, this result is consistent with what I get using LLC Off + offset without Eco Mode. Temps during this run went down to the range of 48-49C. Testing CBR20 ST briefly, I saw temps jumping around between 48C and 52C, with a consistent voltage of 1.38v reported by CPU-z.
In CBR20, Eco Mode + LLC Off + -.1v offset produced temps maybe .5C lower than without the offset. The final score was 6589. Ryzen Master reported once more that the benchmark hit the cap of 87W.
edit edit: just to sanity-check my results, I disabled Eco Mode and went back to my "normal" settings for default operation: LLC Off, -.1v voltage offset. Then I reran SuperPi 1.5 mod XS. Peak voltage was 1.392v (as observed with Eco Mode) and the best result I could return with this config was 9.055s - ever so slightly slower than in Eco Mode. Temps hovered between 44-46C. The CPU actually produced higher temps in Eco Mode in this ST application, and ST performance went up as well (by a tiny bit). CineBench R20 ST showed similar behavior . . . using my "usual" config, the ST bench only caused temps to oscillate between 49-50C (1.38v reported by CPU-z).