RX580 - Maximum memory voltage?

[Jism]

A new bios editor has bin released: https://www.igorslab.de/en/now-also...ly-with-full-support-for-the-older-amd-cards/

I've editted my current bios with it (It holds a 250W TDP) to increase the maximum core voltage that was allowed. I can push 1.3V now in Wattman if desired, where before i was just limited to 1.15v or so. There's another option in there, to increase the memory voltage, and not controller, which i did from 1.1V to 1.2V. Since ive loaded up the 1600Mhz straps onto the 2000Mhz profile, i could bump the clocks now up to around 2140Mhz which is a 100Mhz increase. I see good gains, because if i compare this bench:

With my own, at 72.5 using Ultra quality preset, then i've done a good job so far. I am able to push the core to 1500Mhz, and having it watercooled using a AIO with 2 fans. Max temp? Around 60 degrees. Ive attempted to run furmark, not knowing the extreme preset was turned on, so it kind of peaked to 300W GPU power consumption, my UPS triggering and 22A on the 12V line being consumed, lol.

I think going beyond 1500Mhz from this point is dull; the power consumption and heat will only go up with barely no improvement. How much is this memory (Sapphire RX580 8GB) capable of really? If i am able to push a few more mhz out of it then i might be happy for a good overclock, since the RX580 is pretty much bandwidth starved. More = better.

 

[generaleramon]

Polaris is crazy bandwidth starved, 2150Mhz memory + crazy tight timings are barely enough for 1350-1400Mhz on the core.
sadly the voltage of the memory chips can't be changed via software on polaris cards, is a fixed 1.5v, you can measure it on the output capacitor of the vram vrm. What you can change in wattman is a voltage floor for every memory state, so if at 2100mhz you set 1100mv your vcore is not allowed to go under 1100mv using that vram pstate, just use the lowest voltage possible. I worked on polaris a lot, tested increasing the IMC voltage (can be done in the bios) but i gained almost nothing on both my 2 cards (1000mv on RX480s and 950mv on RX580s), adding 50mv MIGHT help you get 25mhz more, i also tested to hardmod the vram vrm and increased the voltage to 1.6-1.65v, no frequency increase as the limiting factor is the IMC if i guess right... i simply managed to further tighten the timings. i think you just need to find the highest stable frequency, set the lowest floor voltage possible and than lower the timings as low as possible to gain bandwidth. Google "UberTimings", it's my optimized set for Samsung memeory modules.

 

[Jism]

Then what did i increased, on the 1.1V to 1.2V and having a higher, maximum memory overclock from 2040 initially to 2140Mhz now? This is with the 1600Mhz strap applied to the 2000Mhz settings.

Not sure what is better. Or default timings and 2250Mhz + on the memory, or tighter timings + overclock as far as you can go.

 

[generaleramon]

the voltage floor can help, yeah, weird that you need 1200mv for 2140Mhz. How high can you clock the memory (with 0 EDC/Memory errors) on stock timings?

 

[Jism]

I'm not sure. I think it was 2250Mhz / maxed out. I dont have a backup bios from the 2000Mhz straps either and i'm not looking to test / bench all that again.

2140Mhz on top of the already 1600Mhz strap is good.

 

[generaleramon]

try those "UberTimings" i told you about, waaay better than the stock 1600mhz strap. you might even clock the memory a bit higher while getting more raw bandwidth

 

[Jism]

Ok,

loaded up

777000000000000022CC1C00AD615C42F0590F15300D9708006007000B031420FA8900A00300000011112F3FBB354019

which is "Ubermix 3.1" to the 2000 strap and lets see.

"72.7" which is like 0.2FPS increase. The maximum clock for the memory is now 2170Mhz which is 30Mhz more. I woud'nt say that the ubermix was better then the 1600Mhz strap. As for Superposition it increased from max 22.5 fps to 22.7 fps on 1080p Ultra test.

777000000000000022CC1C00EF615C44F0590F15300D070A0060070013051420FA8900A0030000001212303FB2354019

Ubermix 3.4 applied. Now a 73.4 FPS which is overall a 1 FPS increase, lol. The maximum overclock of the memory now is still at 2140Mhz. I think Superposition it went to 23.5 or something.

 

[generaleramon]

try the v3.3 and v3.4 and see if you get better results. going from stock to my timings should give you around 2-5% more performance, as you are starting from the 1600 strap you get less. Be sure to have 0 memory errors. Also try to start from 2000mhz and slowly increase the frequency, stop when the score/fps start to drop. sometimes the card is reporting no EDC errors but performance is degrading. 2100-2150Mhz is usually the sweet spot for these cards. The 590 has a better IMC(+12nm) and can clock the memory higher.

 

[Jism]

Yes, the memory errors are to a zero. 2140Mhz is the best i can get at 1.2V i guess.

On avg the card consumes 180 to 190W on gaming. In furmark this peaks to 300W lol. The temperature on 1500Mhz / gaming does'nt exceed 54 degrees on avg. When furmarking on 250 to 300W we're looking at 64 or so. But furmark is a unreal situation anyway; since there are no games that can make the card work that hard.

This will be the last card before summer ends; then it's big navi.

 

[generaleramon]

Well, with 1500Core+2140Memory+CustomTimings you are almost touching the 250GB/s mark. That's around 40GB/s more than stock. 1500 on the core is way past the voltage/frequency sweetspot so...
Good job, you pretty much maxed out this uArch

 

[Jism]

GPU-Z is reporting 273.2GB of memory bandwidth. Ive seen higher numbers with polaris.

 

[generaleramon]

That's just the theoretical max bandwidth, the real one depends from the core clock + IMC + timings + istructions used. I use OCLmembench or AIDA64 GPGPU to do a fast realworld test