Question OC Ryzen 3900x


Apr 6, 2018
so i recently got the ryzen 3900x (paired with aorus pro wifi x570 motherboard) and was wondering a couple things....

1.) was watching der8auer overclock his 3900x and was explaining some of the overclocking by CCX, which i kinda understand but when i turn off PBo and other automated overclocking stuff to do my overclocking, my TDC and EDC seem to get REALLY high.. over the 95a/140a markings on ryzen master.

2.) also wondering if im doing something else wrong. temps get pretty close to the 85-95 range with a corsair H100i V2, after disabling some stuff for auto oc type of settings and adding turbo power curve for OC stability, is that what is causing my higher temps, and TDC/EDC going nuts?

3.) what do you guys think the VID limit should be? ive been reading from 1.35-1.38 range which seems to be reasonable, but im also fairly new to ryzen.

4.) though i understand silicon lottery, and my luck is the worst you could come across, having a roughly 1200 R15 score difference seems a little far off to me. maybe not.. i can get my CCXs running at CCD0 > CCX0 > 4450 // CCD0 > CCX1 > 4425 // CCD1 > CCX0 > 4350 // CCD1 > CCX 1 > 4350.. which seems kinda slacking to me personally... is my luck realllyyyy that bad or am i missing something?

all help is appreciated :)
3.) what do you guys think the VID limit should be? ive been reading from 1.35-1.38 range which seems to be reasonable, but im also fairly new to ryzen.
Two things about 'Safe Voltage' for Ryzen: first, it's different for each processor. It's determined by testing at AMD and then 'fused' into the FIT curve that's used to govern boosting.

Second: it's not really one voltage but depends on the temperature and clock speed where the processor is operating at the moment; hence it being on a curve. But since you want to fix the clock and voltage while ignoring temperature you'll want to know what's safest for all points on that curve. You can find that out fairly easily:

Put everything to AUTO: auto voltage, auto clocks, LLC disabled, etc. Run an extremely intense process, something like Prime95 but fixed on one FFT size (I use 138K min and max) so it never varies. Let the processor stabilize at temperature, something like 15-20 min's. The algorithm will lower clock speed and voltage to keep a safe temperature ending right around the BASE clock speed located on the box; maybe a bit higher depending on your cooling. For my 3700X that's 3.6-3.625Ghz.

Now, take a look at the (SVI2 TFN) VCore voltage reading that HWInfo64 reports (and NEVER use VID for this). That will be the highest safe voltage for all points on it's unique V-F curve according to FIT and should be used for a manual, fixed clock speed/fixed voltage, overclock if you're also looking for long life. You're challenge now will be to find the highest fixed clock, whether all-core or per-CCX, that will remain stable at that voltage.
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Reactions: Phaaze88


Dec 22, 2016
I've just run r15 and got 3117 and that's with everything on auto. It's pointless overclocking a 3900x, they are already binned to hell, not really thermally dependant when overclocking so you might not even get a stable +100mhz and at stock already beast through everything.