Bitcoin Forum

hello everyone,

I bought new XFX R9 280X graphic card and i have been trying to get it to mine above 700kh/s for a few days. After some tempering with the cgminer settings I discovered that no matter what settings I use if cards temp goes over 65C it becomes unstable and hashrate start to fluctuate between 400-700...as the temps go higher hashrate drops significantly.
For example:
When I use gpu memclock 1500, gpu engine 1055 I get 734kh/s stable (no hashrate dropping) at temp 64C (gpu fans are at 100%)
When I set target temp to 67 I get average hashrate of 650kh/s (jumping from 550-700kh/s)
When I set target temp to 75 I get average hashrate of 580kh/s (jumping from 400-600kh/s) -temp never reaches 75C and cgminer crashes after some time

I have tried setting powertune to 20, installed beta drivers, disabled catalyst,added extra more RAM but with no effect.

What are my options? Will I be able to RMA my card?
Should I run some benchmarks to see if it will show some errors so I can have the valid reason to return it?

There is no way I could maintain such a low temperature of the card especially when I add some more cards to the rig.

Undervolt: https://bitcointalk.org/index.php?topic=395004.0

Seems to have the same BIOS problem some Sapphire cards have with thermal throttling. XFX cards are generally considered to be the one of the worst for mining.

tnx i will check it out

I know...I bought it because it was the only one they had in stock. I know that xfx models in some cases throttle because of higher temperature(over 75-80C) but only 65C??? I didnt see that coming.

Maybe it's time to upgrade to something else.

Check VRM temps. My 280x XFX has 67C with gpu engine 1040, 737 khash, anything higher begin throttling, because VRM temps go till 114C.

https://i.imgur.com/W4T8ZxH.png

everything looks exactly like you said. so we are basically screwed right?  there is no way out of this?

Undervolt !

 :P

yeah I figured...but I doubt it will bring down the temps that much. Also I'm not sure if I will lose warranty when I'm undervolting the card.

hehe

Well, the prospect of losing warranty is indeed a problem. Perhaps you should return it.

Are MSI Afterburner or Sapphire Trixx unable to lower the voltage?

Consider mining non-scrypt coins with it: MemoryCoin, Protoshares, Vertcoin, Maxcoin, Darkcoin, Metiscoin and a few others.

I just found out that my card is not voltage locked so I can change it in TRIXX. Current voltage is 1225. What voltage should I set? (clocks should stay the same right?)

BIOS version is 015.040.000.001

Nice! Start at 1100 mV and go down to ~1000, in steps of 10 mV, for that 1055 Mhz (and some safety). It will lock up, artifact, throw HW errors or appear SICK/DEAD somewhere in the middle if it gets too low. Just pick the lowest voltage you can get it stable and keep looking at those VRM temperatures.

Mine can reach 1100+ Mhz at 1087 mV. Other as low as 1050 mV.

so if I go too low with voltage and graphic crashes when I restart everything should go back to normal? I guess if I ever decide to sell or RMA the card I can switch to factory voltage and no one will ever know I have changed it?
what is your hashrate per card and what are your temps? are your cards placed into case?

When you restart it is back to normal, you need Trixx to reapply voltage. I never saw a card losing warranty by undervolting.

When I mine scrypt, my cards are below 63ºC (I'm sorry I don't remember exactly atm lol), except one. They are in an attic with abundant air circulation and 2 large fans. I have 2 cards plugged on each motherboard (R9-270 + 7870XT, R9-270 + 6950) and others on risers (7970 and 280x's).

nice. I just found my lowest voltage 1093mV. On 1087mV I get BSOD after running cgminer for a few minutes. Power consumption fell 50W after undervolting.
Right now I'm hashing 737kh/s 1060/1500MHz powertune:0 core temp 58C fan 88% VRM temps:92, 90C. I will try to raise more engine clock and see what happens. So far everything looks stable. Thanks a lot

EDIT: now my hashrate cant get above 500kh/s at the same settings for some reason...even if I raise the voltage back like it was previously...

I just reinstalled the drivers and everything went back to normal. Card is undervolted and hashing stable 733kh/s at 50% fan speed. We will see what will happen when I add more cards to the rig and temps got higher.

Fan speed is still too low and voltage too high if your VRMs are at 92ºC. I'd raise fan speed a bit and sacrifice those 33 Kh/s for a bit lower voltage. Perhaps 1075 mV and 1020 Mhz.

ok. I will play a bit more and see what I can come up with. I have a stupid question: why the card voltage is always back to stock value when I restart my computer? how I can avoid that?

RMA that bitch r9s like 80-85c for max performance. nothing over 90 though.

Also 1032 engine, 1500 memory in afterburner is beastmode for 280x.