Very important: always set CCX0 to 50-100mV above CCX1 for 5900Xs and 5950Xs. I.e., 4.7GHz = 4.75 on CCX0 and 4.65 on CCX1.
The Ryzen 5950X is made up of two CCXs. One CCX is excellent and the other is kinda trash. The trash one is what you’d find in the 5800X. They cut down the 8-core CCX to make the 5900X and 5600X, and so on.
The reason the 5950X needs to have an uber-good CCX0 and a fairly decent (better than a 5800X) CCX1 is to keep temps within reason. Basically the CPU has better silicon so it can run less voltage to hit its absolute max clocks.
I spoke to a person who’s an expert on Ryzen for around 8 hours on NAAF’s discord. He’s tuned hundreds of Ryzen systems the same way each time and I’m inclined to agree with his methodology, although I deviate slightly.
Now I don’t know how often Ryzen voltage spikes at idle, but what I do know is that AMD’s algorithm is pretty weird and it’ll feed far too much voltage that what is required for most workloads, especially when dealing with all-core workloads.
To put in perspective, my old 5900X while playing COD MW was boosting itself to 4.55GHz at 1.5V because the temps were sufficiently low and current draw was sufficiently low. I was able to daily 4.6GHz all-core at 1.25V set with 1.2V at load, which yielded 80c-ish in IBT V2, and idle temps that were fairly chilly.
A better way of doing what I did is simply dialling in your RAM settings and voltages rails (manual or just base XMP), disabling stuff like ‘Core Performance Boost,’ ‘CPPC,’ ‘CPPC Preferred Cores,’ and ‘Cool and Quiet.’ Thereafter you need to pick an LLC setting that you’ll end up testing later on. You can grab Ryzen Master on desktop and dial in a fixed core ratio and a set voltage (that’ll be mediated by the LLC setting you picked in BIOS).
Don’t daily anything above 1.3V (TSMC’s white paper limit that I’m inclined to believe after reading numerous accounts online), and also because you’re not going to be cooling any sort of stress test or R23 if you’re running anything above 1.3V set. In fact, I’d be surprised if you could even run 1.25V set on a 5950X and not hit well over 85c in something like IBT V2 or R23.
Even 1.2V load voltage is super high for the R9 parts due to the concentration of heat and the fact that only the Arctic coolers have an offset mount that caters to the CCX placement on the substrate.
In that regard my recommendation to you would be to set a fixed-core ratio at something like 1.25V (you should hit 4.6-4.7 depending on your CPU bin), and set something like LLC medium in your Aorus BIOS (+-40mV) of Vdroop. For some reason my friend had an issue setting a fixed voltage in the BIOS and booting from cold, so I’d recommend using the Ryzen Master method (it also means your CPU will down-clock at idle). Your CPU should be able to run a stress test at +-1.2V load voltage, and in R23 your temps should be reasonable.
Something to keep in mind is that it’s totally normal for your CPU to hit 90-100c in R23. The purpose of AMD’s algorithm is to squeeze as much juice out of your CPU given an envelope of power and heat. If your CPU is under-volted, all that happens is the decreased voltage will allow for more boosting headroom.
My 12900K hits 90-95c in R23 because my daily (and maximum usable) OC is 5.0 P, 4.0 E, 4.0 R at 1.35V set with around 1.3V under heavy load due to the LLC setting on my Asus board. It’s totally normal to have your CPU burn up in a stress test unless you’re using a decked out loop or exotic cooling. At least it is normal when you’re talking about R9’s and i9’s. The current draw of R23 is tremendous, and to run a high-ish all-core on both Intel and AMD requires a fair bit of voltage. Around 1.2V at load for a 5950X at 4.6GHz and around 1.3V at load for most i9’s at between 5.0-5.2 depending on how good your bin is. Multiple either of those numbers by the current draw of R23 (not R20, that’s fairly light).
But yeah… P95, Linpack Extreme, IBT V2, R23, and TimeSpy Extreme Physics; will all push your CPU above and beyond 75c. P95 at the right (or wrong) voltage, could see your CPU hit 110c pretty easily. That’s kinda just the nature of running your CPU at its all-core maximum in a heavy AVX workload. You can’t run the CPU at its max all-core with less than adequate voltage, so unless your cooling solution is insane, 90s are something one just has to get used to under the circumstances mentioned above.
Before someone types a reply:
AMD’s data sheets for Ryzen clearly stipulate an ‘up to’ spec for the boost. The only thing you are promised is base clock. This is in stark contrast to Intel’s fairly strict specifications for what your CPU should be capable of during the warranty period (not accounting for degradation due to manual OCing). I.e., my 12900K from mid-December 2021 till three years after the fact would’ve been guaranteed 4.9 all-core on the P-cores (technically it isn’t anymore).
The Individual I spoke to alarmed me when he explained how AMD’s CPU VID logic works, and it all makes sense when I read about the negative voltage offsets outlined in this thread. AMD’s CPUs know how much they can boost to given a certain amount of voltage. If the chip degrades it simply boosts to a lesser degree than before at the same voltage.
This individual also made a case in which he described an experience he had with two identical sealed 3600X’s. Basically he sent the one with the better silicon to his friend and his friend forgot to enable his OC profile, so his friend ran the chip at stock for 6 months, where after the Individual found that the max all-core dropped from 4.225 to 4.15 I believe.
This is anecdotal so you don’t have to trust it but it makes some level of sense to me judging by the accounts online from some users. Silicon degradation also depends on how perfect your silicon was to begin with.
The fact that under-volting by something like 0.125V is because you’re shaving 125mV off of the CPU’s voltage supply, and it will thus result in significantly decreased load voltage, but also a significantly nerfed boost clock. Instead of setting an under-volt, you’re better off setting something like 1.25V and finding out what your CPU’s silicon quality is like and how high you can manually set the all-core. Other than that you could set 1.2V and have it Vdroop down to 1.1-1.15V under heavy load, and set something like 4.4-4.5 all-core. Clock stability is much better at lower temps and 4.5 @ 1.125V or something to that effect might be achievable on something like a 5950X. That’ll result in something like 78c max in R23 if I had to spitball it.