Question How do I undervolt an XFX Radeon RX 590 Fatboy ?

M Uzair Arshad

Reputable
Jan 3, 2020
70
2
4,545
i have an XFX Radeon RX 590 Fatboy. Currently at 1545mhz core clock at 1150mV. it pulls around 185w at max in game while temperature goes to 74 C max. I have no issue with temperature but i want to bring down power consumption. I have tried multiple combinations for undervolting such as 1510mhz at 1030mV, 1520 at 1110mV. For the first one the power consumption was very good around 160w at max and it boosted fps as well.

These undervolts are stable in Superposition and Rise of the Tomb Raider benchmarks but they would crash in Arena Breakout Infinite and sometimes in Tomb Raider's benchmarks as well. I read somewhere that the
XFX Fatboy edition of the RX 590 cannot be undervolted. Can someone help me with the exact combination for undervolting, or tell me if it is even possible to undervolt the XFX Fatboy edition?
 
possible to undervolt the XFX Fatboy edition
I mean....you've already explained that you've done it, so yes, it's possible.

What you need to understand is that all chips are different (statistically in a sort of bell curve fashion). The exercise of undervolting is simply finding the lowest stable voltage curve for your specific chip. Really the same underlying concept as overclocking (since frequency is typically limited by max voltage these days for the average user).

Generally speaking, I'd say 1510MHz at 1030mV is aggressive, and that 1100mV is probably closer to what you'd expect to be stable.

The game has changed a bit since I sold my RX580, but back then it was important to make sure you're setting a memory voltage that's enough to keep the VRAM from throttling. This effectively acted as a voltage floor for the entire GPU (since the core and VRAM are fed the same voltage). I believe the RX590 acts the same way. The VRAM voltage setting generally doesn't control at the max GPU clock though.
 
Last edited:

M Uzair Arshad

Reputable
Jan 3, 2020
70
2
4,545
I mean....you've already explained that you've done it, so yes, it's possible.

What you need to understand is that all chips are different (statistically in a sort of bell curve fashion). The exercise of undervolting is simply finding the lowest stable voltage curve for your specific chip. Really the same underlying concept as overclocking (since frequency is typically limited by max voltage these days for the average user).

Generally speaking, I'd say 1510MHz at 1030mV is aggressive, and that 1100mV is probably closer to what you'd expect to be stable.

The game has changed a bit since I sold my RX580, but back then it was important to make sure you're setting a memory voltage that's enough to keep the VRAM from throttling. This effectively acted as a voltage floor for the entire GPU (since the core and VRAM are fed the same voltage). I believe the RX590 acts the same way. The VRAM voltage setting generally doesn't control at the max GPU clock though.
Do i need to change vram voltage as well or should i let it stay at default? And i don't understand how should mhz and mV go together. Like should i decrease speed wkth voltage, increase it or let it stay at default? I want to limit power at around 160-170w can you please help me with mV and mhz?

Also what I read on some site is that xfx fatboy cards have some specific capacitors that will cause gpu to crash whenever you change voltage.
 

Imperat0r

Proper
Apr 19, 2024
208
61
170
Hello.
Undervolting a card would make sense if you have a low quality PSU or a PSU that has lower wattage then suggested. Why would somebody undervolt a card that is so old and would not offer enough frames for a current game in high settings?

Is there anything else you wanna share with us ?
For example that card was an ex miner ?
 
Last edited by a moderator:
And i don't understand how should mhz and mV go together.
It takes a given amount of voltage to drive a chip at a given MHz. More MHz = more mV to keep it stable. When chip manufacturers create frequency/voltage curves (for BIOS or VBIOS) suffice to say they generally do a single all-encompassing curve, so that's going to be stable for most/all, but with a varying amount of headroom depending on the quality/characteristics of each individual chip. What you're doing with undervolting is finding the "exact" freq/voltage curve that YOUR chip needs to run stable.

I want to limit power at around 160-170w
You can just lower the power % slider to achieve this. ie, an RX590 is rated for 175W, so 90% power = 158W.

Now....with the "stock" freq/voltage curve, maybe....1500MHz pulls 175W, and 1450MHz pulls 158W. So if you only cap the wattage, you get a maximum frequency of 1450MHz. What undervolting does is to pull (say) 1500MHz from 175W down to 158W. So NOW when you cap the wattage, you still get the "stock" (1500MHz) frequency. Or* if you don't cap the wattage, you get a higher frequency (maybe now 1550MHz = 175W)

^all hypothetical numbers. For example, I run my RTX3060Ti at 60% power limit and an undervolt. This reults in a 5% decrease in frequency compared to stock. FPS isn't measurably different without logging it to a .csv file and doing statistical analysis (which I don't care enough to do anymore these days).
 
Last edited:

M Uzair Arshad

Reputable
Jan 3, 2020
70
2
4,545
Hello.
Undervolting a card would make sense if you have a low quality PSU or a PSU that has lower wattage then suggested.
Why some1 would undervoltage a card that is so old and would not offer enough frames for a current game in high settings?
Is there anything else you wanna share with us ?
For example that card was an ex miner ?
well my card is good, not mined at all and i have 60hz screen so it can pull 60 fps in nearly every game at high settings. Psu is good as well I just want to decrease power consumption.
 

M Uzair Arshad

Reputable
Jan 3, 2020
70
2
4,545
It takes a given amount of voltage to drive a chip at a given MHz. More MHz = more mV to keep it stable. When chip manufacturers create frequency/voltage curves (for BIOS or VBIOS) suffice to say they generally do a single all-encompassing curve, so that's going to be stable for most/all, but with a varying amount of headroom depending on the quality/characteristics of each individual chip. What you're doing with undervolting is finding the "exact" freq/voltage curve that YOUR chip needs to run stable.


You can just lower the power % slider to achieve this. ie, an RX590 is rated for 175W, so 90% power = 158W.

Now....with the "stock" freq/voltage curve, maybe....1500MHz pulls 175W, and 1450MHz pulls 158W. So if you only cap the wattage, you get a maximum frequency of 1450MHz. What undervolting does is to pull (say) 1500MHz from 175W down to 158W. So NOW when you cap the wattage, you still get the "stock" (1500MHz) frequency. Or* if you don't cap the wattage, you get a higher frequency (maybe now 1550MHz = 175W)

^all hypothetical numbers. For example, I run my RTX3060Ti at 60% power limit and an undervolt. This reults in a 5% decrease in frequency compared to stock. FPS isn't measurably different without logging it to a .csv file and doing statistical analysis (which I don't care enough to do anymore these days).
i have tried 1530mhz at 1110mV it was running good in furmark, rise of tomb raider benchmark, played arena breakout for around 20 minutes but then later i was playing ROTR and it crashed about half hour into the game
 

Imperat0r

Proper
Apr 19, 2024
208
61
170
Well, as @tennis2 said, you can achieve that goal by using the software settings.
I would put at 1190 mV.
At least that is what i did when i used to flash my cards for mining.
Indeed i had only 2 RX590 among them, but all the rest were RX580.
After that you will decrease further the Mhz, in order to achieve the stability at that voltage..
After all, you need to test the computer for hours and hours until you are pleased with the outcome.
 

M Uzair Arshad

Reputable
Jan 3, 2020
70
2
4,545
Well, as @tennis2 said, you can achieve that goal by using the software settings.
I would put at 1190 mV.
At least that is what i did when i used to flash my cards for mining.
Indeed i had only 2 RX590 among them, but all the rest were RX580.
After that you will decrease further the Mhz, in order to achieve the stability at that voltage..
After all, you need to test the computer for hours and hours until you are pleased with the outcome.
1190 or 1090? Also today i will try UV with afterburner. Can you tell me is undervolting safe right? like if my gpu crashes multiple time etc etc its safe? it won't hurt my hardware?