Bitcoin Forum

Hello gus..

I have some rigs with RX 480 cards (5 or 6 cards each one) and i use 2 psu x 850W in each Rig.

Now i am making some R9 390 rigs.. But i can see that i will need at least 850W PSU for 2 cards.. I tryed to power on 3 cards on a 1000W gold plus PSU and sometimes it goes off..

Is this normal?  ???

Undervolt those 390s. 3 should work on a 1000W PSU.

3 on 1000W should do the job, try undervolting maybe? (- 100mv)

I run 3X 290 on a 850W...

Hey, maybe you can try to modify server PSU. They are much more stable under load and much more efficient than normal PSUs. I saw a lot of guys do that so i did it few months ago and it's working fine under full load (1000w). You can search this forum, a guy posted tutorial few years back, and best of all 1000w PSU i found for less than 50$

1000w gold psu should easily feed 3x390 everything default.

thats not correct friend..

Sometimes a R9 goes to 400W 3x400 = 1200W

If you use dual mining ETH + DECRED for example, unfortuny this happen.. (on stock)

You are right, forgot someone could be dualmining.

Give me one example where 1000w can't feed 3x390, launch config. I will try it right away.

i tryed here with zcash v8 (works)

the problem on my rigs with psu is when i use this:

Claymore's Dual Ethereum+Decred_Siacoin_Lbry AMD+NVIDIA GPU Miner v7.3
6 x r9 390 (powercolor)
2x 1000W gold plus PSU

tryed on 2 rigs

1 - Work for 4 hours than reset
2 - Reset after 20 minutes (and i thought the psu was broken, but is wasa not)

So you have two 3x390 rigs? Or two 6x390? Or one 6x390 rig powered by 2x1000w psu?

i made the test in 2 Rigs

each one has the same conf. (6 x r9 390 - 2 x 1000W PSU)

TOTAL:
12 x r9 390 - 4000W

Ok, give me your .bat file, one 3x390 ready with power meter.

this is my .bat file:

And your core/mem/power settings?

All Stocks...

http://image.prntscr.com/image/35843660c8bf47a4a673cf49fe527103.png

Looking at your .bat it is not your psu. I will try to mine for you anyway.

Try to lower that intensity.

sorry friend, i give you the incorrect .bat...


the correct one is from dual miner:

1060w at the wall, how long do I need to run this?  8)

edit: 29 eth + 435 dcr if someone is interested.

1060 for how many cards?

3  ;D

Nice tests friend...

1060 is just a little bit higher then 1000. Maybe undervolting is a good choice...

Or maybe buy more PSU... Or use rx480 😀

No need to buy psu's, your settings are way off. I just wanted to do stress test with some lunatic settings.

You on nix or windows?

Windows 10 64bits

Stop that dual mining.

Install gpu-z and msi afterburner.

Download hawaiireader.

On gpu-z, extract your bios.

On hawaiireader, open that bios and look what those dpm clocks are. Use those dpm 2-7 core + mem 1500.

Do some more powersaving with afterburner.

Do some serious powersaving with bios modding.

nice tips..

Cheaper than buy more PSU's

:)

How much power it can be saved with bios modded? And how it'll affect the hash power? (Let's saying if one card consume 120w)

Well it depends, 100% if you shut down your rig  ::).

290/ 390(x) can be whatever you want it to be. Powersaver? sure, it can do 270. Compute monster? No problem, how many watts?

If you want to find those very best settings you need to go gpu by gpu. It takes 'some' time, add different algos and miners and you are so lost.
Start with those basic settings and do some google if you want to know more.

 For stock cards, or cards with a mild undervolt and a lot of overclock, you're looking at probably 300ish watts PER CARD.

 If you can get them undervolted enough and don't push them super hard, 1000 watts for the entire system should be viable but might still be marginal.

 Don't forget the rest of the parts in your system also eat SOME power, not just the GPUs.

 Also, not all "1000 watt" power supplies are created equal, though MOST "gold-rated" should be able to handle their 1000 watt ratting for a while at least.
 You might also need to check how the +12vdc power rails are set up on your power supply, you might be overloading one specific rail and not the whole PS.


 For reference, the R9 390 is a R9 290 with slightly faster memory and an updated BIOS - my "bigrig" with 3x R9 290s using a modded TheStilt "undervolt+tighten up timings+turn off some of the ROPs" bios goes through a little over 1000 watts at the wall with the cards clocked at 1100/1250 on ETH mining (reference cards stock clocks 947/1250).

QuintLeo,

Your volts?

I think I'm running the "3'd step down" TheStilt bios varient on them - haven't thought about it in months as they've just been working rock-solid.
I don't remember what the voltages were on each varient, but it was a fairly small incriment per step.

 Did I remember to mention that they run 15 degrees C or so cooler despite being able to overclock to 1100 instead of thermal limiting at the stock 947 before the bios change?