VDDIO safe ranges and effect on stability (AMD)

[dis]

Does anyone know what the safe range is here?
I've seen buildzoid ramping up to match CDD & VDDQ voltages 1.4c etc, but my bios (x870e aorus master) keeps it at 1.1v while set to auto

Could just be a BIOS bug, or an intentional limit (i do *not* like the gigabyte bios). I've seen Asus boards that suggest vSOC < VDDIO < VDD/VDDQ, my bios tells me nothing.


I'd leave it alone, but 1.1v to 1.25v has allowed me to lower ram timings. Lot of testing to finish before calling it stable, but seems to have had an effect.

I'm looking for long term stable overclocks, and am cautious about pushing 1.4v etc though there if it's going to cause issues 1-2 years down the line.

 

[Jamin280672]

Ive run VDDIO on my ASUS board at 1.45v without issue for as long as I can remember, newer bioses seemedd to fix it not needing so much, im not so sure I would push it any further than that, but my CPU is under water, so it does depend on you cooling and how far you want to push your ram, these voltages are mostly in your CPU, so cooling plays a big part, VDDIO, SOC and obviously VID are all CPU related voltages, some boards label it as VDDIO / MC (memory controller) voltage.

Heavy RAM overclocks can be a PITA, especially trying to figure out which voltage is causing the problems, so I normally start at the upper end with VDDIO @ 1.45v, VDDP @ 1.15v and SOC @1.25v, then play with VDD and VDDQ whilst trying to get RAM overclocks stable, once stable, I work on getting VDDIO, VDDP and SOC down one at a time, its certainly not a 5 min overclock, more like a week or 2 of constant adjustments and testing.

For instance, even though my sticks are rated for 8400, I couldnt get tPHYRDL to match, the only way was raising VDDP, this is why I start at 1.15v with this one, its currently at 1.08v, but anything lower and they mismatch again, auto gives 1.05 which is a mismatch.

I got VDDIO down to 1.38v and SOC down to 1.18v, again anything lower resulted in errors.

 

[ATIorNvidia]

What speeds are you trying to achieve? There's a very large range of settings that will just work in 1:1, whereas 2:1 will require significantly more fine tuning.

 

[dis]

Ive run VDDIO on my ASUS board at 1.45v without issue for as long as I can remember

Cool, that's the reassurance i was looking for.
Would be super handy if the BIOS would show recommended ranges. I like tweaking, i don't like killing silicon early.

What speeds are you trying to achieve?

Nothing crazy, just tweaking. I'd like 6400 but that seems off the table without vSOC above 1.3

Currently running 1:1 @ 3100 - Buildzoids easy Hynix m-die configs (with a few relaxed timings), fclk 2067.
vSCO 1.18, VDD/VDDQ 1.35-138, VDDIO 1.35


The BIOS ended up switching from 1.1 to 1.35 for VDDIO on auto, and i assume it's not trying to cook my hardware, so i've left it there. Will test it later, see where it gets unstable when lowering


It's been interesting, i know a heck of a lot more about RAM timings than i did two weeks ago. The impact of tREFI / tRFC was unexpected (but makes sense)
Still, i've only gained 2-4% over EXPO settings. If i could hit 6400mt, maybe 5-6%.

Only other gain left is testing high FCLK. 2200 seems stable, 2233 POSTs but hits issues (need to play with vSOC, see if higher/lower helps. But doubt it'd ever be trustworthy. Just interested to run some speed tests)

 

[GoRedwings19]

Does anyone know what the safe range is here?
I've seen buildzoid ramping up to match CDD & VDDQ voltages 1.4c etc, but my bios (x870e aorus master) keeps it at 1.1v while set to auto

Could just be a BIOS bug, or an intentional limit (i do *not* like the gigabyte bios). I've seen Asus boards that suggest vSOC < VDDIO < VDD/VDDQ, my bios tells me nothing.


I'd leave it alone, but 1.1v to 1.25v has allowed me to lower ram timings. Lot of testing to finish before calling it stable, but seems to have had an effect.

I'm looking for long term stable overclocks, and am cautious about pushing 1.4v etc though there if it's going to cause issues 1-2 years down the line.

Well generally my ram is like 1.45v. But I wanted to lower my cas latency. Now I am aware that cas latency has a very low impact as it has been well documented it not a thing on Ryzen cpu's. So my Ram at c38 is 1.45v but I saw a few peeps who could run this ram at C32. Great I thought. However while it may run at C32 you do have to pump in a lot of voltage and you need cooling on the ram sticks. I just plonked a fan on top.

So for me to run the mem at 8000 c32 2200 fclk I need 1.25v Vsoc. 1.69 VDD and 1.67 VDDQ and a fan to cool it. It has been rock solid but there would be no way I would run it without a fan and the only reason I decided to learn about ram overclocking properly is becuase I got the mem for cheap otherwise I wouldn't of bothered.