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AMD RX 7000 series GPU Owners' Club

Also different samples of a GPU will run at different minimum voltages under a small or frequency-limited load. Not sure if this is simple silicon lottery or something more broadly a manufacturer does or similar things done to a particular model of GPU (like all 7800 XTs).

However based on my my experience with a pairs of AMD GPUs (soon to be another pair), it seems to be silicon lottery. I have two 5600 XTs, which is a core clock speed-limited GPU (1780 MHz hard limit) and one runs at 956 mV and the other at 912 mV stably. Power use and performance is within margin of error and both are Sapphire Pulses, though one is the original and the other is the BE revision (an excuse to include a less overkill cooler). So very likely silicon lottery differences. Minimum voltage is also different between the two, in the 760 mV range but I haven't tested that recently so I don't have the exact figures for those.

On my RNDA 2 GPUs, minimum voltage on the 6600 XT is around 660 mV while my 6700 XT is ~860 mV and my 6800 XT is around 780 mV. Nothing consistent there and others have screen grabs with their (actually good) 6700 XTs running in the 700 mV region. Seems like silicon lottery again.

I see some 7900 XTXs here running at 690 mV while my 7700 XT won't go below 860 mV.

Silicon lottery dammit.
 
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Also different samples of a GPU will run at different minimum voltages under a small or frequency-limited load. Not sure if this is simple silicon lottery or something more broadly a manufacturer does or similar things done to a particular model of GPU (like all 7800 XTs).

However based on my my experience with a pairs of AMD GPUs (soon to be another pair), it seems to be silicon lottery. I have two 5600 XTs, which is a core clock speed-limited GPU (1780 MHz hard limit) and one runs at 956 mV and the other at 912 mV stably. Power use and performance is within margin of error and both are Sapphire Pulses, though one is the original and the other is the BE revision (an excuse to include a less overkill cooler). So very likely silicon lottery differences. Minimum voltage is also different between the two, in the 760 mV range but I haven't tested that recently so I don't have the exact figures for those.

On my RNDA 2 GPUs, minimum voltage on the 6600 XT is around 660 mV while my 6700 XT is ~860 mV and my 6800 XT is around 780 mV. Nothing consistent there and others have screen grabs with their (actually good) 6700 XTs running in the 700 mV region. Seems like silicon lottery again.

I see some 7900 XTXs here running at 690 mV while my 7700 XT won't go below 860 mV.

Silicon lottery dammit.
Here you go
Screenshot 2024-08-13 130151.png
 
Also different samples of a GPU will run at different minimum voltages under a small or frequency-limited load. Not sure if this is simple silicon lottery or something more broadly a manufacturer does or similar things done to a particular model of GPU (like all 7800 XTs).

However based on my my experience with a pairs of AMD GPUs (soon to be another pair), it seems to be silicon lottery. I have two 5600 XTs, which is a core clock speed-limited GPU (1780 MHz hard limit) and one runs at 956 mV and the other at 912 mV stably. Power use and performance is within margin of error and both are Sapphire Pulses, though one is the original and the other is the BE revision (an excuse to include a less overkill cooler). So very likely silicon lottery differences. Minimum voltage is also different between the two, in the 760 mV range but I haven't tested that recently so I don't have the exact figures for those.

On my RNDA 2 GPUs, minimum voltage on the 6600 XT is around 660 mV while my 6700 XT is ~860 mV and my 6800 XT is around 780 mV. Nothing consistent there and others have screen grabs with their (actually good) 6700 XTs running in the 700 mV region. Seems like silicon lottery again.

I see some 7900 XTXs here running at 690 mV while my 7700 XT won't go below 860 mV.

Silicon lottery dammit.

You're right. After watching around a dozen RDNA3 UV tutorials, it seems like 'traditional' undervolting is dead and buried with RDNA3. From what I can tell, voltage is now tied with frequencies and the voltage slider is actually a voltage 'percentage' slider. Took me a while to wrap my head around it as I'm an old man who's been undervolting long before it became a thing i.e via BIOS modding!

Now, I've one final question before I finally pull the trigger:

I'm interested in a 7700XT, a 250W card. From what I can tell, most cards only allow up to a -20% power limit which means 200W. and that's still too high for what I've in mind. Question is, would I be able to force a 40-50% power limit via something like More Clock Tool so that it consumes right around 120-130W of power while pushing around 1.6 to 1.8 GHz (depending on the silicon lottery)?

It seems like the utility has an option to adjust GPU power limit, though I'm not sure if it can go below 20% factory default.

1723576305680.png
 
You're right. After watching around a dozen RDNA3 UV tutorials, it seems like 'traditional' undervolting is dead and buried with RDNA3. From what I can tell, voltage is now tied with frequencies and the voltage slider is actually a voltage 'percentage' slider. Took me a while to wrap my head around it as I'm an old man who's been undervolting long before it became a thing i.e via BIOS modding!

Yes but the slider behaviors are very similar in RDNA2 as well.

Now, I've one final question before I finally pull the trigger:

I'm interested in a 7700XT, a 250W card. From what I can tell, most cards only allow up to a -20% power limit which means 200W. and that's still too high for what I've in mind. Question is, would I be able to force a 40-50% power limit via something like More Clock Tool so that it consumes right around 120-130W of power while pushing around 1.6 to 1.8 GHz (depending on the silicon lottery)?

My Pulse 7700 XT only allows a -6% power reduction. FREAKING USELESS! I'm mildly annoyed by this, can you tell?

Instead you can just go the older route of setting a frequency limit like 2500 if you want to hit lower power (with your card's stable undervolt curve of course). However I'll follow up with saying that my card only gets down to about 860 mV (I have too many cards to remember exactly) and that's at about 2200 MHz and 135W (those are correct). Stock is 220W on my card so that's not quite 40% lower power. Below that any efficiency is gained purely by lower clocks but not lower voltage so the small power savings are not worth it IMO. I do run at 2200 a lot for most of my VSYNCed games and turn it up for the newer higher demand games I play.

Based on other posts here and my other GPUs, minimum voltage and therefore optimum efficiency points seems to be a crapshoot, different for each individual GPU.

It seems like the utility has an option to adjust GPU power limit, though I'm not sure if it can go below 20% factory default.

View attachment 358809

I need to try that as I prefer limiting by power than clock speed.
 
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I need to try that as I prefer limiting by power than clock speed.

Power limiting definitely sounds much more convenient than tinkering around with the V/F curve and crossing your fingers.

You can also test if MCT can override the 860mV voltage limit on your particular variant.

Awaiting your input.
 
Power limiting definitely sounds much more convenient than tinkering around with the V/F curve and crossing your fingers.

You can also test if MCT can override the 860mV voltage limit on your particular variant.

Awaiting your input.
I like these experiments...
Get ready to study

Using Superposition (game mode) in windowed mode and altering settings on the fly
Going from 400+W to <130W

On first image clock and voltage are stock. On the second shot doing some UV only
Clock gone up, voltage drop and power stays the same.
From there starting first by limiting power and then next manually drop clock.
Pay attention also to the last 2...

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I like these experiments...
Get ready to study

Using Superposition (game mode) in windowed mode and altering settings on the fly
Going from 400+W to <130W

On first image clock and voltage are stock. On the second shot doing some UV only
Clock gone up, voltage drop and power stays the same.
From there starting first by limiting power and then next manually drop clock.
Pay attention also to the last 2...

I see. It seems like the voltage floor is 650mV on your particular variant. I must say it's impressive to see sub 150W power consumption as it's actually comparable to a GTX1060 or an RX470.

In any case, how far can you push frequencies at 650mV, if you don't mind me asking?

I'm assuming it should be able to push around 1,300-1,500 MHz at ~650-700mV by lowering the voltage slider down all the way and raising the frequency slider up to around 1,500 MHz or so?
 
Not sure the point, considering how the new GPUs do clocking. Just FPS limit to your desired needs and it will be same as power limiting, chicken or egg....
 
Can’t remember if I actually joined the club since I upgraded to Powercolor Hellhound 7900XTX. I’ve been a Sapphire guy since the 9800 but I have to admit this probably one of my favourite cards I’ve ever owned.
IMG_0199.jpeg
 
I think that is lowest possible. Mine runs about the same
Below this I guess its shutdown time...
Nahhhh.

You guys have too much going on, on screen :)

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When I start dragging windows, frantically clicking and mousing I get this, which is seemingly the desktop-ish load state it stays at too. But its very, very fine grained nowadays. I did not see this low on my 8700K based system though.

1723649945383.png


Not sure the point, considering how the new GPUs do clocking. Just FPS limit to your desired needs and it will be same as power limiting, chicken or egg....
Not so sure that's true. You'd have to set different FPS limits per game. If you don't cap off your clock, the GPU will run a much higher wattage when you run heavier games as it needs more oomph to clock higher. If you set a clock cap, there will still be great variance, but you can control and cap the peak power, to a very big degree. An FPS cap won't.

Even with a max clock cap, you will still have games that suck all the juice they can get, for example Cyberpunk or some UE5 content where it is exceedingly harder for the GPU to run at max clock under low voltage as you stress almost every bit the GPU has. The peak clock will automatically be lower, so its closer to your defined max, so you get closer to peak (stock) wattages. That's perhaps the better situation to apply an FPS cap in the game to improve frame stability and save power, on top of your max clock cap.
 
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Nahhhh.

You guys have too much going on, on screen :)

View attachment 358951

View attachment 358958


View attachment 358959

When I start dragging windows, frantically clicking and mousing I get this, which is seemingly the desktop-ish load state it stays at too. But its very, very fine grained nowadays. I did not see this low on my 8700K based system though.

View attachment 358960


Not so sure that's true. You'd have to set different FPS limits per game. If you don't cap off your clock, the GPU will run a much higher wattage when you run heavier games as it needs more oomph to clock higher. If you set a clock cap, there will still be great variance, but you can control and cap the peak power, to a very big degree. An FPS cap won't.

Even with a max clock cap, you will still have games that suck all the juice they can get, for example Cyberpunk or some UE5 content where it is exceedingly harder for the GPU to run at max clock under low voltage as you stress almost every bit the GPU has. The peak clock will automatically be lower, so its closer to your defined max, so you get closer to peak (stock) wattages. That's perhaps the better situation to apply an FPS cap in the game to improve frame stability and save power, on top of your max clock cap.
I saw the same thing during the day. Lowest it went was 14 watts. and 225mv
 
Not sure the point, considering how the new GPUs do clocking. Just FPS limit to your desired needs and it will be same as power limiting, chicken or egg....

This is how I do it and it works.

And if you're into tinkering and finding the lowest power use, there is more efficiency to be gained as when playing a low-demand game like Rocket League at 1440p/144Hz, many GPUs will boost to their set voltage and then clock down the cores but not always keep the voltage reduced. That is: the voltage alternates between a low clock-appropriate voltage and the max voltage as set by the card's curve. This wastes power, sometimes a lot of it. Both AMD and Nvidia GPUs do this but not every one.

The solution there (if this kind of stuff is your thing) is to set the max boost clock to a lower number, well within the GPU's efficiency zone. This is very easy in AMD's software and more annoying but equally doable in Afterburner for Nv cards. For lower demand games where 60 fps is great so your GPU is at 2/3 load or lower, doing this can save 35% power which in the summer is always a nice benefit for lower heat output. Also it's fun!
 
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Nahhhh.

You guys have too much going on, on screen :)

View attachment 358951

View attachment 358958


View attachment 358959

When I start dragging windows, frantically clicking and mousing I get this, which is seemingly the desktop-ish load state it stays at too. But its very, very fine grained nowadays. I did not see this low on my 8700K based system though.

View attachment 358960


Not so sure that's true. You'd have to set different FPS limits per game. If you don't cap off your clock, the GPU will run a much higher wattage when you run heavier games as it needs more oomph to clock higher. If you set a clock cap, there will still be great variance, but you can control and cap the peak power, to a very big degree. An FPS cap won't.

Even with a max clock cap, you will still have games that suck all the juice they can get, for example Cyberpunk or some UE5 content where it is exceedingly harder for the GPU to run at max clock under low voltage as you stress almost every bit the GPU has. The peak clock will automatically be lower, so its closer to your defined max, so you get closer to peak (stock) wattages. That's perhaps the better situation to apply an FPS cap in the game to improve frame stability and save power, on top of your max clock cap.
Some times in the past right after upgrading drivers I did saw 9~11W total board power, but thats only for short time. After usage, restarts and so... it bottoms at 25~30W or 45~50W depending on whats going on on screen. Also the TBP fluctuates a lot along with VRAM speed. Could be my display settings...

I see. It seems like the voltage floor is 650mV on your particular variant. I must say it's impressive to see sub 150W power consumption as it's actually comparable to a GTX1060 or an RX470.

In any case, how far can you push frequencies at 650mV, if you don't mind me asking?

I'm assuming it should be able to push around 1,300-1,500 MHz at ~650-700mV by lowering the voltage slider down all the way and raising the frequency slider up to around 1,500 MHz or so?
On Superposition load manage to run 1200MHz with 687mV but keep in mind that this is a big GPU and most likely well binned as the top variant of 7000series.
Different variants like 7900XT, 7800XT, 7700XT should have different results about their V/F curves and I even expect differences between the same variants (of different vendors or even from same vendor).

Lowest possible clock was 600MHz with 654mV and kept that voltage until ~700MHz
Refused to go under 600MHz. Was dialing 550, 599... and after "Accept" was back at 600MHz

The weird thing was that after 1200MHz (1250, 1300, 1500...) kept running at 1200MHz and ~687mV
Only at ~1800MHz (1801MHz exactly) got up there with ~730mV
And when I took the opposite road it slowed down to ~1200MHz/687mV at 1799MHz setting

Here...

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BTW the settings of Superposition on all screenshots and from previous post was at game mode static, no movement as follows

1723653946178.png
 
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Lowest possible clock was 600MHz with 654mV and kept that voltage until ~700MHz
Refused to go under 600MHz. Was dialing 550, 599... and after "Accept" was back at 600MHz

The weird thing was that after 1200MHz (1250, 1300, 1500...) kept running at 1200MHz and ~687mV
Only at ~1800MHz (1801MHz exactly) got up there with ~730mV
And when I took the opposite road it slowed down to ~1200MHz/687mV at 1799MHz setting

I've seen that same kind of unpredictable behavior on my 7700 XT. When I'm running low clocks in the ~1500 MHz zone it "wants" to stick to one or the other of the Min or Max frequencies even though the GPU demand is 100%. It should go to max but sometimes it doesn't. The algorithm behind all of this is seems not to be optimized for these kinds of underclocking experiments.
 
Powercolor Hellhound 7800XT uses PTM, or the equvalent TIM, so I'd guess any higher end Powercolor will use it.
Oh, that's good to know. Source? Nothing about PTM in TPU's review.
I was thinking about ordering PTM and new thermal pads. Card gets a bit toasty for my liking, but Powercolor support said that it's all good. They did not mention PTM when I asked them about pad thickness and warranty if I do it. According to them it voids warranty and they did not have the thickness... so that was a waste of time
 
Oh, that's good to know. Source? Nothing about PTM in TPU's review.
I was thinking about ordering PTM and new thermal pads. Card gets a bit toasty for my liking, but Powercolor support said that it's all good. They did not mention PTM when I asked them about pad thickness and warranty if I do it. According to them it voids warranty and they did not have the thickness... so that was a waste of time
They can say whatever suits their profits. If they can find the slightest excuse to avoid RMA, they will find it.
The thing is, what is "legal" or not and we as customers are lacking big time on that knowledge.
I've seen and heard GamerNexus Steeve saying that such a thing does not really exist. They can put as many red stickers as they want on the backplate screws.
I can't really confirm.
 
I can't really confirm.

As a RMA tech I can confirm, broken VOID seal is not enough to reject warranty.

Manufacturer repair guidance do tell you that actually, it is a warranty void reason(They do tell many stupid things to save them money) and if the service location is pretty idiot, like Steve had, then shit happen. But normally, like in my case we take into account local consumer laws and are the middle men negotiating... if something is wrong not the the manufacturer is sued but the local contractor.
 
It probably has no weight, but I just thought to ask at the same time I was asking about pad measurements.
 
Powercolor 7900 GRE Red Devil. Unable to oc VRAM past 2280mhz, which is 30mhz more than stock.

Anyone else have a GRE that behaves like this?

vram.png
 
I seem to be stable running it at this.
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Powercolor 7900 GRE Red Devil. Unable to oc VRAM past 2280mhz, which is 30mhz more than stock.

Anyone else have a GRE that behaves like this?

View attachment 359343

I have multiple samples from 4 different GPUs (R5 240, GTX 745, RX 5600 XT, RTX 3050 6GB) and the VRAM OC capability in all pairs varies more than the GPU core OC. Looks like you got the low end of the VRAM OC like my 6700 XT has the low end of the GPU OC (it cannot reach listed boost clocks but does pass stock clocks). Sorry man, bad luck.
 
I have multiple samples from 4 different GPUs (R5 240, GTX 745, RX 5600 XT, RTX 3050 6GB) and the VRAM OC capability in all pairs varies more than the GPU core OC. Looks like you got the low end of the VRAM OC like my 6700 XT has the low end of the GPU OC (it cannot reach listed boost clocks but does pass stock clocks). Sorry man, bad luck.
Not gonna lie, it's pretty damn good as it is. I just saw a slider that goes to 3000 and thought it might move further than 2280 without insta crashing.

Also Hardware Unboxed mentioned this in their review of the GRE and this was meant to be being changed.
 
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