Sapphire vega 64 UV/OC adventure

[Toy Machine]

Afternoon All

I received my Vega 64 LE and I want to tweak it to find a good 24/7 ECO UV to keep the card temps down and maintain similar performance.

My goal really is to stay under 200w consumption and keep temps below 75c. I am willing to sacrifice clock speeds for noise, as the main thing I want to achieve is how silent I can get this card with tinkering and obviously maintaining as much performance as I can.

My main goal with this is UV and bringing down the power consumption and therefore thermals. And in turn stabilize the clock speeds, being at 1080p, I do not need the peak performance out of the card and to really push it. Stability is the key here.

I'm asking for anyone who owns or knows the tricks to do this, what kind of clocks and mV I should be setting on the Power states and what are good baselines to work off of.

HBM is always set to 1000mV @ 950mV power to the memory. (925mV if P6/7 is at 950mV to the core)

I have gone as low as 950mV on P6/7 and I seem to always be capping out at 1450mHz
Fan RPM is capped to 2800rpm and keeps temps around 75c and Hot spot under 90c. This only holds if I am under 1v to the core in P6/7, anything higher and I get to 80c.
I don't want to push the fan over 3k RPM because of acoustics.

I tried an UV where peak power draw is 190w, with P6/7 @ 1537 & 1600 mHz both @950mV
With this, I hang around 1440mHz and temps hit 75/76c max. I really like this, but I am concerned that there is too little power going to the core for a long period of time and do not want to cause harm to the card. I want stable and safe clocks. Above all a healthy card.
I say this is too low because when I am playing games (only tested in R6S for a few minutes) but I am drawing 80-100w which I think is crazy low and so may not be healthy to be that low.

If I draw 200w in a bench test (I use Superposition) then I draw around 160-180w in-game.

I will try and upload pictures but Carb doesn't seem to like it for some reason, I upload to imgur and then Carb always says the link is invalid.

 

[Toy Machine]

Has anyone with this card had HWinfo or something detect tremendous spikes in temps? Two seperate instances of the PC being on, I've had Hotspot and GPU temp spike over 1,000c according to HWinfo64. I can understand it being a spike and maybe misreading the actual temp, but I want to find out if that is something to be concerned about and if it can have an affect on the card.

 

[Toy Machine]

Decided to run some more testing.

All benches were done in Heaven 4.0 1080p extreme Fullscreen. I wanted something that I can loop and do this one test on.

This time I went from stock settings and only down clocked the power to the core, did not touch the Core clocks, I'm trying to find a point where it will artifact/crash.

Anything above 1050mV to the core resulted in almost immediate thermal throttling as it took less than 30secs / 1min to hit 85c on core & 90c on Junction temp.

Core Clock: 1536/1630 mHz
Core Voltage: 1.2-1v
HBM clock: 950mHz
HBM Voltage: 1.1v - 950mV
Fan speed capped at 2500rpm. (undoubtedly higher RPM will allow the thermal headroom to push further.

Core Voltage will mostly only represent P6/7 states. all other states are brought down -25mV once P6/7 hit the lower states mV's except for P1, left at stock and slight adjustments made to the 25mV range on states 2-5.

I found no artificating in any of the ranges and only found a crash once I set P6/7 to 975mV where I hit a crash. Lowering P6/7 would negate that as I have run 950mV P6/7 @ 1500/1550 mHz stable.

All scores ended up sub 2000 but as I lowered CV from 1.2v the scores degraded down to about 1800 (between 18-1900) highest was at stock around 1950-70.
Most if not all was caused by thermal throttling, as soon as you hit 83-85c Core would drop from 1500mhz - often 1200/1200 mHz on the core, making the average just over 1310mhz.

It got interesting once the Core was dropped to 1050mV P6/7 - This allowed the card to take longer to hit 85c, but also hold a lower avg. temp at around 75 - 80c
Not only that, but the core held higher clocks overall, even when throttling, because it wouldn't throttle as badly it would mostly stay above 1400mHz when it did. Anything under 85c would see the core holding just above 1500mHz and as such 1025mV & 1v to P6/7 yielded less temps and higher scores.

From 1050mV P6/7 I broke into the 2000 score range, with 1v bringing to 2121 I believe to be the highest I hit now.

I kept HBM 25mv under Core Voltage and left it at 950mHz throughout. My card doesn't like 1100mHz on HBM and only seems to get to 1075mHz once I go to 975mV to juice it there. It holds 1000mHz stable @ 950mV which I am yet to put in for this run of tests, I know it produces higher FPS and is an area that shows a good amount of gain rather than just core tweaking, as the power delivery for the HBM is just more core voltage essentially.

Edit: I was going to upload pictures but seems they all saved to some random format so no pics.

 

[RuskaDP]

@Toy Machine
Check out this thread - Calling all VEGA 64 owners to join in (under volt / overclock achievements) | DIY / Modding

 

[Ebrahim Ali]

Whats your thermal paste situation? Your card gets realy hot for a LC edition.

I found that lowering voltage under 1v sees clocks fall of a cliff, whereas once you would get 1500mhz+ you now only manage 1300mhz - 1400mhz.
Best compromise i reached was 1,1v to the core and 1.05v to the HBM. with fan speeds set to spin all the way to 70% at 65 degrees I consistently see core cloks in the high 1500mhz range. On especially cold days I can go past 1600mhz.

Your undervolt seems a bit extreme. Try lowering to 1.05v or 1v and keep the core clocks at stock. You should hit your power and temp targets. Also make sure your thermal paste and thermal solution are in good shape.