Question RX 580 8gb boost clock power limit and undervolt

kknd2

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I recently bought a 2nd hand rx 580
https://www.newegg.com/Product/Product.aspx?Item=N82E16814137244

all the setting changes i've done in MSI afterburner. I reinstalled AMD software, but while installing, i only installed the driver and HDMI audio (there were 2 other boxes i didnt tick, one was amd setting or something, i can't remember what the other was)

this card advertised to have 1340 mhz boost clock.
I cannot get to this frequency. it hovers around 1250 mhz ish. (max temp was around 64c)

I managed to get 1340 mhz by increasing the power limit to 22% (now new max temp was around 70c)



my question is is it normal to have to increase power limit just to reach boost clock frequency? shouldn't the card reach this out of the box without any fiddling?




I later decided to undervolt and its stable with -50 mv.

so now it is using around 1060mv at full load. (max power is around 66c)




my 2nd question is this seems odd to have to increase power limit, and then undervolt the gpu. why is this (the increase power limit) needed?




using the 2019 19.4.3 driver

running r7 1700 @ 3.8mhz

16gb ddr4 ram

750w PSU


the perious amd gpu i used was a HD6850. so i have not seen this "increase power limit" thing.

thx
 
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Jimcuchim

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I think it's because it's second hand. Most of the time, a second hand object is probably second hand because it is broken or some weird stuff happens to it, it is not often that the previous owner got a new one right after they got it. So have a not so good clock is not so weird.
 

kknd2

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I think it's because it's second hand. Most of the time, a second hand object is probably second hand because it is broken or some weird stuff happens to it, it is not often that the previous owner got a new one right after they got it. So have a not so good clock is not so weird.

hang on, i always thought electronics (computer parts) either just work or they don't. I dont think a slight performance degradation happens in gpus. am i wrong in this?

so it is not odd to have to increase power limit to just hit the advertised boost clock of 1340 mhz?

also i"ve taken the gpu a part and gave it a clean scrub and new thermopaste*
 

Jimcuchim

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True. Normally they they won't decrease performance much after a long time. But unless the previous owner extremely overheat it. But GPU is much more heat resistant than a CPU. Or maybe the previous owner undervolted the GPU first.
 

kknd2

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Oh, sorry, I mean that AMD just released the RX 580 only in 2017. So it is quite new. Only 2 years, so the owner probably can't hurt it too much.
I did some research.

apparently it is possible for a 2nd hand gpu to have been used for mining. often miners mod their gpu bios since apparently mining requires mostly vram and not much for the core (i don't do any mining). is it possible that this gpu i'm using is not running a MSI factory bios?
 

PC Tailor

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You can check the BIOS version of your GPU. But there are other things to consider first before jumping to a GPU flash.

You shouldn't need to up your power to get to boost clock - but the boost is dependent on other conditions. In effect if you are operating well within power and temperature ranges, the GPU will in a sense "auto-overclock".

Do you have latest GPU drivers installed?
How are you trying to reach your "clock" speed? Are you doing this whilst under load? It won't boost if it doesn't need to.
What temperatures are you reaching on your GPU?
 

Wendigo

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all the setting changes i've done in MSI afterburner. I reinstalled AMD software, but while installing, i only installed the driver and HDMI audio (there were 2 other boxes i didnt tick, one was amd setting or something, i can't remember what the other was)
What about giving a try to a default installation of the software package ?
 

kknd2

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You can check the BIOS version of your GPU. But there are other things to consider first before jumping to a GPU flash.

You shouldn't need to up your power to get to boost clock - but the boost is dependent on other conditions. In effect if you are operating well within power and temperature ranges, the GPU will in a sense "auto-overclock".

Do you have latest GPU drivers installed?
How are you trying to reach your "clock" speed? Are you doing this whilst under load? It won't boost if it doesn't need to.
What temperatures are you reaching on your GPU?

without increasing power limit to 22% in msi afterburner, the clock speed boosts up to around 1240-1260 mhz while the gpu is at 100% usage. (temp is around 64c)
with power limit (to 22% in msi afterburner), the clock speed boosts up 1340 mhz (as the card is advertised) while gpu is at 100% usage. (temp is around 70c)

this card continues to have 1340 mhz (with 22% power limit) even after i undervolt to a -50mv (dropped to around 1060mv while @ 100% usage, the temp is around 65-66c)


right now the problem i have is atiflash does not work with windows 10 1809 update (which is driving me crazy). I need to install a lower windows onto an usb or something. GAH!!!
 

TJ Hooker

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You shouldn't need to up your power to get to boost clock - but the boost is dependent on other conditions. In effect if you are operating well within power and temperature ranges, the GPU will in a sense "auto-overclock".
It's not uncommon for RX 580s to fail to hit rated boost clocks under heavy load due to power limit, especially budget cards like the OP got.

It may be worthwhile checking the vBIOS, but most cards with mining BIOSs would have their core clock set lower and the fact that the card gets up to 1340 MHz without having to make any adjustments to core clock suggests this isn't the case.
 
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kknd2

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It's not uncommon for RX 580s to fail to hit rated boost clocks under heavy load due to power limit, especially budget cards like the OP got.

It may be worthwhile checking the vBIOS, but most cards with mining BIOSs would have their core clock set lower and the fact that the card gets up to 1340 MHz without having to make any adjustments to core clock suggests this isn't the case.

can you explain why some rx 580 fails to hit rated boost clock due to power limit then?

if it needs more power to hit 1340 mhz. then how come my rx 580 is still at 1340 even though i've heavily undervolted it? it seems like a "+1 -1 = 0" scenario.
 

TJ Hooker

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can you explain why some rx 580 fails to hit rated boost clock due to power limit then?

if it needs more power to hit 1340 mhz. then how come my rx 580 is still at 1340 even though i've heavily undervolted it? it seems like a "+1 -1 = 0" scenario.
Different models of RX 580 come with different power limits. Some premium cards will use binned chips that require less power to run at a given speed. VRM quality/efficiency may also be a factor.

If you're hitting the power limit you can mitigate this by either increasing the power limit or undervolting (or some combination of the two). But it will never boost higher than the core speed that is set, i.e. 1340 MHz, unless you manually increase that speed.
 
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kknd2

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Different models of RX 580 come with different power limits.Some premium cards will use binned chips that require less power to run at a given speed. VRM quality/efficiency may also be a factor.

If you're hitting the power limit you can mitigate this by either increasing the power limit or undervolting (or some combination of the two). But it will never boost higher than the core speed that is set, i.e. 1340 MHz, unless you manually increase that speed.

isn't undervolting the same as giving the gpu less power (or electricity)? and increasing power limit is to permit the gpu to get more power (electricity) from the PSU? I feel confused.
 

TJ Hooker

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Yes, lowering voltage will lower the power consumption for a given frequency. And increasing the power limit increases the max amount of power the card is allowed to draw. I'm not sure where your confusion is coming from. If your card is hitting the power limit you can work around this by either lowering the power being used (undervolting) and/or increasing how much power it is allowed to draw (increasing power limit).
 

kknd2

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Yes, lowering voltage will lower the power consumption for a given frequency. And increasing the power limit increases the max amount of power the card is allowed to draw. I'm not sure where your confusion is coming from. If your card is hitting the power limit you can work around this by either lowering the power being used (undervolting) and/or increasing how much power it is allowed to draw (increasing power limit).

say the gpu pulls 180 watt of power by stock. it gives 1250 mhz clock speed. I increase the power limit by 22%, the gpu now pulls 200 watt ish of power, and is giving 1340 mhz clock speed.

i then under volt the gpu by 50%. it drops down to 160 watt ish while still giving 1340 mhz of clock speed.

why is it that this gpu can only yield 1340 mhz with a higher than stock watt AND a lower than stock watt. but not at the stock watt. this is what i'm confused about.
 
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TJ Hooker

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why is it that this gpu can only yield 1340 mhz with a higher than stock watt AND a lower than stock watt. but not at the stock watt.
As I said above: if the core clock is set at 1340 MHz, it won't boost higher than that. If you want the clock to go higher you need to manually increase it (in Afterburner/Wattman/whatever). It will then boost up to whatever you set it too, assuming it's still withing power/thermal limits.
 

phdibart

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say the gpu pulls 180 watt of power by stock. it gives 1250 mhz clock speed. I increase the power limit by 22%, the gpu now pulls 200 watt ish of power, and is giving 1340 mhz clock speed.

i then under volt the gpu by 50%. it drops down to 160 watt ish while still giving 1340 mhz of clock speed.

why is it that this gpu can only yield 1340 mhz with a higher than stock watt AND a lower than stock watt. but not at the stock watt. this is what i'm confused about.
I'm with kknd2...I just don't get it, and I'm in the same boat. My RX580 (different card than the OP) won't hit boost clocks unless I increase the power limit.