MP All Models Sapphire PULSE RX580 8GB VBIOS Study

h9826790

macrumors G5
Original poster
Apr 3, 2014
14,387
6,943
Hong Kong
*** For info, this mod is NOT compatible with the OpenCore boot screen mod ***

This thread is about how to mod the Sapphire PULSE RX580 8GB card's ROM image. If you worry about bricking the card, or void the warranty etc. STOP HERE!

For those who has MVC flashed RX580. Do NOT perform this mod. Any modification of the ROM will disable the Mac EFI UGA. And do NOT even try to flash the dumped (MVC) ROM back onto the card. Even this action may cause problem. As general rule, NEVER touch the MVC flashed ROM.

I had no plan to write this at the beginning, therefore, not everything has good records. Some info are just from my memory, may not be 100% correct. If you have different info (better with prove), please correct me ASAP.

Background

So far, all AMD GPU that I own are shipped with unnecessary high voltage (in fact, same on my 1080Ti, but just not that bad). e.g. My Sapphire HD7950 Mac Edition card come with default 1.094V, but actually the GPU can run stably at 0.888V. That's 23% above the required voltage. Most of the extra voltage (power) will be converted to heat, which just a waste of power, make the card run hotter, and most likely shorten the life span as well.

Therefore, when I got my Sapphire PULSE RX580 8GB. One of the very 1st thing I did was to test how much voltage I can reduce. As expected, the RX580 also come with unnecessary high voltage. My card can run stably at 1.00V, but it default to run at ~1.15V. Not as ridiculous as the 7950, but still 15% too much.

If the card has a decent cooler, that's not a problem. However, the PULSE cooler seems not quite good enough in hot Asia. The card can run into thermal throttling when stressed.

This was captured when my RX580 doing the Furmark benchmark (It's just the benchmark, not the stress test).
1366 Furmark.jpg

The card can draw slightly above 75W from the slot, and tiny bit above 150W from the 8pin (combined Booster A and B, the two orange lines on the left side). And it is throttled to 1263MHz during the benchmark, fan already running at the "max" 2280RPM, temperature go above the target 75C (the highest I've seen so far is 84C).

Yes, Furmark is a bit too extreme, then how about "normal" high stress?
1366 VAlley.jpg

The card can stay within the designed power envelope. Clock speed can stay at 1366MHz. Not bad. However, still run above the target temperature 75C (vary between 75-80C). Fan still stay at the max 2280RPM. The card isn't that noisy, but I still want to further reduce it.

So how to?

The Sapphire PULSE RX580 ROM

This is how the default ROM image looks like in PolarisBiosEditor 1.6.7 (a Windows software)
RX580 native.PNG

As you can see in the FAN section (lower left part), the Target temperature is 75C. From my observation, the card will allow the GPU keep warming up and only slowly spin up the fan. Once reach 75C, the fan will spin up more and more to keep the GPU at 75C, until the fan reach the max RPM 2280 (which is just 60% PWM).

And in the POWERTUNE section, we can see that the TDP of the card is actually 145W. And Max Power Limit is 155W HOWEVER, the POWERPLAY part also stated that Power Control Limit is 30%. Therefore, 145W x 130% = 188.5W, and 155W x 130% = 201.5W. So, in any case, it fit the official info "below 225W" on the Sapphire web site. And from the Furmark test, we know that the card's power draw is really maxed at ~225W. So, it's actually a very accurate description.

If we further study the POWERTUNE section, then we will know the card's Max temperature is 84C (this can be reached with the native setting), and shutdown temperature is 94C.

Procedure

To mod the card's VBIOS, we need Windows and two other softwares

1) Latest ATIWinFlash
2) PolarisBiosEditor 1.6.7

I did all the followings on my cMP 5,1, Windows 10, and RX580 is the ONLY GPU installed.

First of all, nun ATIWinFlash as Admin, then press "Save" to dump the ROM
ATIWinFlash.PNG


Then keep this master ROM image at a safe place. Copy it to somewhere else (e.g. the Desktop), then you can open the copy of the ROM image by PolarisBiosEditor. And all you need to do is just click the item that you want to mod, change the number at the bottom windows, then click APPLY CHG. End up you should have something like this
RX580 mod.PNG


I did three things in this ROM.

1) I modded the GPU clock speed
2) I modded the GPU voltage pointer
3) I modded the memory voltage

After finished, double check the numbers, then "SAVE AS" a new ROM image. e.g. RX580_mod.ROM (ALWAYS ONLY save as new ROM, NEVER cover your original ROM image)

Then we can use ATIWinFlash to flash the modded ROM back onto the card. If you follow the above procedures, ATIWinFlash should be still opened, but if not, remember to open it as Admin.

Click "Load image" to select "RX580_mod.ROM".

Then click "Program" to flash the card. DO NOT DO ANYTHING until flash complete. It may shows "not responsive" for a few seconds, that's somehow normal, DO NOT DISTURB IT!

Once finish, you can reboot back to macOS. The procedure is done.

What we actually did

What I found is that the Sapphire PULSE RX580 ROM has 2 loops. If we directly insert a voltage for the GPU core, that can only change the 1st loop parameter, the 2nd loop will treat this as an invalid data and ignore it, then go back to the original voltage. Therefore, even I know my card can run at 1000mV very well, I can't force the card to do that via this VBIOS editor.

TBH, up to this moment, I am still not 100% sure if I change the voltage pointer to 65283 has any effect or not. I have no time to test it yet. But what I am sure is that the Sapphire PULSE RX580 ROM is not that fragile, a wrong parameter in the GPU core voltage 1st loop won't brick the card. So, we can just make the 65284 or higher pointers all to 65283. This is a known safe mod for this ROM, at worst, just no effect. Also, it seems the card can automatically select a correct voltage to fit your GPU's silicon with this pointer. This is why we don't need to go through all the stress test before we mod the ROM. This setting is actually very very safe in my own test.

Memory voltage is the same, I tested my card's memory can run at 975mV stably in Wattman. I am quite sure mod the memory voltage to 975 in this BIOS editor has no effect at all. However, doesn't really matter, safe to mod.

Then, we come to the most important part, the GPU clock speed. Why is it important? Because this control the voltage more than anything else. What I found is with the pointer 65283. The GPU will run at

A) ~1.13V when clock speed at 1366MHz (This is why I said this pointer is safe. The card still running at around the original voltage)
B) ~1.07V when clock speed at 1300MHz
C) ~1.02V when clock speed at 1243MHz (stock clock speed for the WX7100)

So, it seems the 65283 pointer still has little effect, the card running tiny bit below 1.15V. But doesn't really matter, we found the key...... the clock speed.

Simply down clock the GPU to 1300MHz, then GPU voltage will automatically reduce to ~ 1.07V, this is actually good enough to keep the card never run above 75C already (except Furmark). Fan speed never reach 2280RPM in my own test with ambient temperature 34C, air-conditioning OFF. And the funny thing is that I found there is virtually no performance difference between this setting and the stock setting.

May be because the stock setting will run into thermal / power throttling. Therefore, the card can't really always stay at 1366MHz. But since I monitored the clock speed with 2 seconds interval, I simply missed the clock speed fluctuation. Anyway, the main point is, basically no performance penalty (in Luxmark), also the card run cooler and quieter.

I was't plan to write this post at the very beginning, therefore, didn't keep that screen capture. BTW, 1300MHz with voltage pointer 65283, from memory, the GPU alway stay at 75C or below, and the fan only go up to ~1850RPM in the Unigine Valley test loop.

Use the WX7100 setting

WX7100 use the same chip as RX580, but it's a 130W TDP single slot work station card. So, what will happen if we use the WX7100's setting?
WX7100.PNG

(Max GPU clock 1243MHz, voltage pointer 65283, max memory clock 1750MHz, memory voltage 975mV)

The result is really good!
1243 Valley.jpg


The card's power draw during Unigine Valley loop drop from 183W to 138W (peak 193W vs 143W). This roughly match the WX7100's TDP. However, since we have a double slot wide dual fan cooler on the PULSE RX580. The GPU never goes above 75C, and the fan RPM is just 1350RPM. Really very quiet.

But, we down clocked quite a lot now. Is the penalty significant? Yes, it's noticeable.

My tests shows up to ~7% penalty in benchmarks. So, if you want squeeze all possible performance from the card, this is definitely not the best setting for you. However, if you don't mind to take few % penalty, or you won't continuously stress the card to 100% for a prolong period of time (e.g. main usage is FCPX), I found this setting is actually very good. Now, no matter how I stress the GPU, I can still hardly hear the fan. And if we run Furmark again. The max draw from slot now become ~70W, and the 8pin pull up to ~140W. Really ALWAYS stay within the cMP limit now (if you care about this).

If you really want to use this setting but minimise the performance penalty at the same time. You can apply the "ONE CLICK TIMING PATCH". In my test, with the memory timing patched, the performance hit will further reduce to about 3%. Very negligible in most real world situation.

High performance mod

If you read this thread is because you want more performance from the RX580, this part is for you.

After multiple tests. I found that my Sapphire PULSE RX580 8GB with voltage pointer set to 65283 can run at 1340MHz @~1.1V (Note 1). Also, my card's memory can run at the Max Memory Freq 2250MHz flawlessly with that "ONE CLICK TIMING PATCH" (voltage still set 0.975V).
RX580_fast_memory_PN.PNG


This is just good enough to let the card stay at or below 75C with fan speed stabilised at tiny bit below 2280RPM (system ambient 34C, PCIe fan ~1900RPM)


With this setting, my RX580 that can performan almost 20% faster in Luxmark (the stock setting usually score at ~15000), without any thermal / power throttling, and never go above 75C.
Screen Shot 2018-08-24 at 01.16.48.png


HOWEVER, if you want to go this way. I highly suggest you MUST first test this setting (especially the memory clock 2250MHz) in Wattman (it's included in the Windows AMD driver package). Make sure it's stable. Otherwise, if your card cannot boot stably after VBIOS mod, it may be very hard to recover. Remember, the PULSE (V1) is a single ROM card. If you brick it, you really brick it (for those have the dual ROM V2 PULSE RX580, you are safe to test any setting you want).

Also, there is no way to tell if the one click timing patch is stable for your card. All I can tell is it works on mine. Use it with caution!

(Note 1: About 10 days after I do this high performance mod. I found that the "silent mode" of the Nitro+ RX580 is also default at 1340MHz. So, obviously it's not a co-incident, but both Sapphire and me found the same sweet spot for this GPU :D)


-----------------------------------------------------
For Advance users only. If you want the GPU to run at an even lower voltage (that the voltage pointer can't do), you may follow this guide to limit the Max Vcore.

https://forums.macrumors.com/thread...-8gb-vbios-study.2133607/page-4#post-26993165
 
Last edited:

pablos

macrumors newbie
Feb 24, 2016
9
3
The latest top of the line 5K iMac are shipped with RX580. Do you think it would be possible to flash the sapphire pulse with this rom?

If so, I can have it extracted and post it here.

Also I am planning to purchase this card, but there seems to be some inconsistency in product naming.
Is the Sapphire Pulse Radeon RX 580 8GD5 Lite 11265-05-20G the same as the card you are working with?

Sapphire Pulse Radeon RX 580 8GD5 Lite 11265-05-20G is currently available on German amazon for around 300 euro,
link here:
https://www.amazon.de/Sapphire-Puls...76&sr=1-1-fkmr0&keywords=saphire+pulse+rx+580

but here in Poland I can have the card "Sapphire Radeon RX 580 Pulse 8GB DDR5 256bit" for around 220 euro. It's the one on the picture attached. Which do you think is the right one?

Screen Shot 2018-08-23 at 10.31.29.png
 

h9826790

macrumors G5
Original poster
Apr 3, 2014
14,387
6,943
Hong Kong
The latest top of the line 5K iMac are shipped with RX580. Do you think it would be possible to flash the sapphire pulse with this rom?

If so, I can have it extracted and post it here.

Also I am planning to purchase this card, but there seems to be some inconsistency in product naming.
Is the Sapphire Pulse Radeon RX 580 8GD5 Lite 11265-05-20G the same as the card you are working with?

Sapphire Pulse Radeon RX 580 8GD5 Lite 11265-05-20G is currently available on German amazon for around 300 euro,
link here:
https://www.amazon.de/Sapphire-Puls...76&sr=1-1-fkmr0&keywords=saphire+pulse+rx+580

but here in Poland I can have the card "Sapphire Radeon RX 580 Pulse 8GB DDR5 256bit" for around 220 euro. It's the one on the picture attached. Which do you think is the right one?

View attachment 777397
I believe both are the right card. Never heard PULSE RX580 lite, the pictures in that page also just the normal PULSE RX580. So, better go for the cheaper one.

And NO, the iMac's 580 won't help.
 

bsbeamer

macrumors 68040
Sep 19, 2012
3,731
1,966
The 11265-05-20G part number for the "Lite Einzelhandel" model is the same as this US/North American model that I just picked up on sale for backup purposes and/or Mojave usage. Have not yet opened the box or tested anything with 10.13.6. Currently using an NVIDIA GTX 1080 FE with NVIDIA web drivers and it's a great card. Hope to continue using in 10.14, but at worst will dual boot the machine for a few years and swap GPUs between both OS's. Likely will need to keep for at least 2-3 years for contractual/legal purposes. (Hopefully more clarity on 7,1 and "Pro" Mac future by then!)

Sapphire PULSE RX580 card I picked up:
https://www.amazon.com/dp/B06ZZ6FMF8
 

crjackson2134

macrumors 601
Mar 6, 2013
4,741
1,897
Charlotte, NC
The 11265-05-20G part number for the "Lite Einzelhandel" model is the same as this US/North American model that I just picked up on sale for backup purposes and/or Mojave usage. Have not yet opened the box or tested anything with 10.13.6. Currently using an NVIDIA GTX 1080 FE with NVIDIA web drivers and it's a great card. Hope to continue using in 10.14, but at worst will dual boot the machine for a few years and swap GPUs between both OS's. Likely will need to keep for at least 2-3 years for contractual/legal purposes. (Hopefully more clarity on 7,1 and "Pro" Mac future by then!)

Sapphire PULSE RX580 card I picked up:
https://www.amazon.com/dp/B06ZZ6FMF8
I installed this card today and I'm having a couple if problems with it. Not sure if it's normal or not.

My computer now says it's not compatible with BootCamp Assistant, refuses to bless the bootcamp drive (even using terminal commands). And I get strange graphical glitches on shutdown. It looks like 2 wide lightning bolts across the screen starting from top left corner. A couple if times it filled the whole screen.

Wondering if I got a defective card now.
 

bookemdano

macrumors 65816
Jul 29, 2011
1,374
761
I installed this card today and I'm having a couple if problems with it. Not sure if it's normal or not.

My computer now says it's not compatible with BootCamp Assistant, refuses to bless the bootcamp drive (even using terminal commands). And I get strange graphical glitches on shutdown. It looks like 2 wide lightning bolts across the screen starting from top left corner. A couple if times it filled the whole screen.

Wondering if I got a defective card now.
Nope, I get this trying to run Boot Camp Assistant in Mojave PB7 with my RX 580 installed:

Screen Shot 2018-08-23 at 5.35.56 PM.png


I bet this is another hard-coded restriction put into place since the lack of EFI precludes using the Boot Picker to get back to macOS :(

Edit: I've also seen white artifacts in the very upper left corner of the screen on reboots.

So... inquiring minds want to know... does this message not occur when running a 7950 or other EFI GPU? We already know the FV2 block doesn't discriminate, so I highly doubt this one does either.

And when were these blocks put into place? Is anyone still running an old Mojave beta and can test for their presence? If they were added in recent betas then it was probably as a result of bug reports.
 

crjackson2134

macrumors 601
Mar 6, 2013
4,741
1,897
Charlotte, NC
Nope, I get this trying to run Boot Camp Assistant in Mojave PB7 with my RX 580 installed:

View attachment 777520

I bet this is another hard-coded restriction put into place since the lack of EFI precludes using the Boot Picker to get back to macOS :(

Edit: I've also seen white artifacts in the very upper left corner of the screen on reboots.

So... inquiring minds want to know... does this message not occur when running a 7950 or other EFI GPU? We already know the FV2 block doesn't discriminate, so I highly doubt this one does either.

And when were these blocks put into place? Is anyone still running an old Mojave beta and can test for their presence? If they were added in recent betas then it was probably as a result of bug reports.
I did manage to boot windows 10 however. After I ran the terminal command, I moved the card into PCIe slot 2 and pulled my SSUBX SSD. On power-up it booted straight into windows.

In fact, I'm typing this in windows right now.
It wasn't occurring for me earlier today when I had my HD5870 installed. It just started as soon as I changed out my GPU to the RX580.
 

bookemdano

macrumors 65816
Jul 29, 2011
1,374
761
Interesting. Maybe BCA is checking the installed GPU then? We'll need more people to test this.
 

h9826790

macrumors G5
Original poster
Apr 3, 2014
14,387
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Hong Kong
How can I check if the memory of my RX 580 Pulse is Samsung?
The PolarisBiosEditor will automatically detect the VRAM manufacture, you don't need to select it by yourself. If you open thunder72fr's ROM, you will see SAMSUNG automatically shows up in the VRAM section.
RX580 Samcung.PNG
 
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orph

macrumors 68000
Dec 12, 2005
1,884
391
UK
just got a rx 580 pules, an X-mining card :rolleyes: the bios i got with it was, just odd (good for mining i gess? was told it crashed when you tryed to play a game :D wonder why lol)
my RX 580 has an asic quality of 68% which sounds low (at least compared to my gtx 660 & 770 which are around 90% i think)
mining bios.PNG
grabbed a bios from techpowerup (the newest one for the RX 580 pulse) no idea if it matters which one i use?
flashed.PNG
iv started playing with wattman, tad confused but think im making some progress and looking for advice (did some google looking but all the hits are about mining settings :mad: which just confuses me)
so far iv played with under volting getting to
gpu undervolt setings.PNG
which seems stable during benchmarks and drops power use to around 120w-133w (mostly 126w).
if i push the 7th state to 1360 at same voltage i get a crash when ruining "Superposition Benchmark"
also get the same score as the default bios (from the web) but not pulling 155w and much much lower temps.
any advice on changing that curve or voltage, this is all new to me.

i tryed playing with the vram settings but if i boost the vram speed from 2000mhz to 2100mhz i start seeing gpu memory errors in hardware info 64, so not shore what to do there.

im hoping to get some help to dial in any changes before i try re flashing anything (i dont even know if i have the correct or best default bios :oops: a new world to me)

edit
vram 2000mhz 975mv is stable (no gpu mem errors in HWINFO64)

do i need to use the mem timing button before i can boost the speed or is it just my card's max potential ?
 
Last edited:

h9826790

macrumors G5
Original poster
Apr 3, 2014
14,387
6,943
Hong Kong
just got a rx 580 pules, an X-mining card :rolleyes: the bios i got with it was, just odd (good for mining i gess? was told it crashed when you tryed to play a game :D wonder why lol)
my RX 580 has an asic quality of 68% which sounds low (at least compared to my gtx 660 & 770 which are around 90% i think)
View attachment 787589
grabbed a bios from techpowerup (the newest one for the RX 580 pulse) no idea if it matters which one i use?
View attachment 787591
iv started playing with wattman, tad confused but think im making some progress and looking for advice (did some google looking but all the hits are about mining settings :mad: which just confuses me)
so far iv played with under volting getting to
View attachment 787615
which seems stable during benchmarks and drops power use to around 120w-133w (mostly 126w).
if i push the 7th state to 1360 at same voltage i get a crash when ruining "Superposition Benchmark"
also get the same score as the default bios (from the web) but not pulling 155w and much much lower temps.
any advice on changing that curve or voltage, this is all new to me.

i tryed playing with the vram settings but if i boost the vram speed from 2000mhz to 2100mhz i start seeing gpu memory errors in hardware info 64, so not shore what to do there.

im hoping to get some help to dial in any changes before i try re flashing anything (i dont even know if i have the correct or best default bios :oops: a new world to me)

edit
vram 2000mhz 975mv is stable (no gpu mem errors in HWINFO64)

do i need to use the mem timing button before i can boost the speed or is it just my card's max potential ?
Yes, this looks like a mining setting. Low GPU clock, low voltage, high VRAM clock and tight timing.

In my own test. That 950mV in the ROM will do nothing. It's just the number in the first loop, and will be overrode by the 2nd loop. The card can draw less power simply because it's down clocked to 1200MHz.

Since we have no idea if this is mod from the original ROM, or it's already a random ROM available on the internet. I will say it won't be more reliable then the Techpowerup ROM, Especially the last owner doesn't even know the 950mV has no effect on the PULSE. We have no idea if anything more in the ROM is modded.

The Techpowerup ROM should be quiet safe for your card. In this case, if I were you, I will flash that ROM to the card first, and then play around in Wattman to see if less crash happen. Your "original ROM"'s timing may be too tight and causing crash. Flash it with the Techpowerup ROM should allow you "start from scratch".

Also, in Wattman, please make sure you set Powerplay to 130%. Otherwise it can't simulate the power draw, temperature, etc in macOS.

If hardware info 64 shows memory error, then don't use that memory clock speed.

And no, no need to apply timing patch to get high VRAM clock speed.
 

orph

macrumors 68000
Dec 12, 2005
1,884
391
UK
my test's where all done on the Techpowerup rom, so been working from there and just changing things in wattman so far.

wanted to check with you before i re flashed the card

edit
so in osx10.13 it's set to +30% power lol did not see that coming from apple
 
Last edited:

orph

macrumors 68000
Dec 12, 2005
1,884
391
UK
was going to try to put lots of work in to figure it out but it is tempting to just use your rom.
what kind of power use do you see with your settings ?
 

orph

macrumors 68000
Dec 12, 2005
1,884
391
UK
ok i flashed with thunder72fr bios, looks good
vram timeings have been already edited (Samsung at least) used OCLMembench to check vram speed
original bios 197gb/s
thuder bios 223gb/s

but it may be a tad to far undervolted for my gpu (i have 68% asic so maybe neeeds more power) struggles to boost past 1300mhz and crash if i try to up the power limit in the amd drivers (in win 7)

so is it best if i change the last two gpu settings to "6584" to add a touch more voltage ?
 

h9826790

macrumors G5
Original poster
Apr 3, 2014
14,387
6,943
Hong Kong
ok i flashed with thunder72fr bios, looks good
vram timeings have been already edited (Samsung at least) used OCLMembench to check vram speed
original bios 197gb/s
thuder bios 223gb/s

but it may be a tad to far undervolted for my gpu (i have 68% asic so maybe neeeds more power) struggles to boost past 1300mhz and crash if i try to up the power limit in the amd drivers (in win 7)

so is it best if i change the last two gpu settings to "6584" to add a touch more voltage ?
Of course you can try 65284, should be virtually no risk.
 
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orph

macrumors 68000
Dec 12, 2005
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im going to give it a few days before i re flash, in windows power seems tad high on the bios but in osx 10.13.6 it seems to only hit around 60w/60w/60w power pool (ie 180w max) according to hardware monitor & im getting high benchmarks in osx
Screen Shot 2018-09-24 at 10.57.30 pm.png
Screen Shot 2018-09-24 at 11.03.21 pm.png
in davinci resolve 15 im getting constant FPS :D that matches my video project (simple project 4K h264 simple grading) my old gtx 770 with CUDA was not able to do that with this project (and only pulling around 90w max for the gpu as i play with the project)

only problem seems to be in windows it's reporting a max closer to 212w (i think) 212W max out.PNG
and core is not able to hit 1340 in the superposition benchmark, just bounces around 1290-1312 non stop (that image is from ruining the benchmark.

ill give it a few days then maybe drop core clock to 1300 and not boost voltage, 40mhz is nothing so dont think it's worth it for me to push that far & resolve is a dream now compared to my old gtx 770

wish there was a app in windows that showed power draw like in osx, hardware info seems not able to see all the power draw sensors and cpu z only gives you gpu core power pull

side note seems the windows (7 only?) drivers at the mo are a tad buged and vram readings in some apps hit 4GB then drop down to 100mb and work back up.

edit
just found out activity monitor show's GPU use !!!!
thats relay cool
https://developer.apple.com/documen..._monitors/monitoring_your_mac_s_gpu_activity/
Screen Shot 2018-09-24 at 11.36.40 pm.png
(that screen shot is resolve exporting a 4K project to prores 422 proxy, relay cool to see such high gpu and cpu use :D)
 
Last edited:
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orph

macrumors 68000
Dec 12, 2005
1,884
391
UK
still playing around in windows watching the card and reading up online.
looks like gpu core voltage cant be drooped lower than vram voltage
https://www.reddit.com/r/EtherMining/comments/7rtu8f/polaris_bios_editor_voltage_issue/
tested in wattman with thunder72fr's bios, as soon as i drop vram voltage core voltage drops inline.
ie
at idle my card pulls 0.975v but if i change vram to 0.95v gpu core drops to the same but cant see any idle power use difference

next iv been playing with mhz/voltage a bit

tests done in win 7 with heaven benchmark (my card is 68% asic may be worse for power use)
-no changes in wattman 1340mhz core i see 1.15-1.16v 160-180w
-wattman set to 1340mhz i see 1.15v 130-160w
-wattmam set to 1330mhz i see 1.137v 120-150w
-wattman set to 1320mhz i see 1.125v 120-150w
-wattman set to 1300mhz i see 1.05-1.06v 110-130w

in windows iv got wattman set to 1300mhz and it seems to load on restart & for me is much nicer (fans are much slower) so next weekend i may just re flash the bios with 1300mhz and see how it go's

maybe also try pointer 65284 at 1340mhz first to see if there's any change but im fairly happy and dont know if i want to spend ages playing around with this.

looks like i may be able to underclock better like i can in wattman if i spend more time but not shore it's worth it :D
still looks like i cant push my vram past 2000mhz without errors but maybe that's linked to my card being used to mine before i got it :confused: or Samsung mem or idk

edit
best stress test so far is superposition benchmark set to "game" then "cinematic mode" in top left which looks like a "free" way to get the stress test option in the benchmark section.
ill re test there later
(i dont like furmark as it seem's to just push to hard so sticking to more normal tests)

edit 2
ok with vram set to 1v i can hold 2250mhz vram with no errors in HWINFO (later edit i did get errors after a while )

iv now hit the point that im done XP spent to much time on this. this weekend ill just flash with a drop down to 1300mhz core and not touch ram speed, if after flash voltage pulled is close to what it pulls in my tests (and power pull in osx is good) then im done
 
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