Why is one 7850 at 78 degrees, but other two at 54 and 57?

[BigJim]

These 3 cards are identical Gigabyte HD7850's 2GB. Why is one 7850 at 78 degrees, but other two at 54 and 57? Each and are pumping out 362kh each.

Identified them by stopping the fans with my hand to see which one heats up or cools down. Tried re-seating the heatsink on the hot card and putting some better paste. Can't figure out why one of my GPU runs 20 degrees C hotter than the other two. All are hanging freely in the air and have decent airflow.

I am using this command...
cgminer -o http://coinotron.com:3334 -u **** -p **** --scrypt --gpu-fan 0-100 --gpu-engine 1050 --gpu-memclock 900 --intensity 12 --thread-concurrency 13632   --gpu-threads 2

GPU-Z shows all 3 cards all running fans at 100%. Only strange thing is one of the cards is showing a higher VDDC. But this is not the hot card! Any ideas?

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[aigochamaloh]

Silicon differences perhaps? RMA the card and replace it maybe.

[ajg007]

Not sure on your configuration,  are these cards Housed in something or in open air?

Its possible that the card in question is not able to remove the hot air away from the card, hence the higher temp.

[BigJim]

open air. what's a good excuse to RMA the card?

[talexeh]

Can you get us a photo of your rig? In most cases, this is due to the position of the graphic cards.

[BigJim]

Can you get us a photo of your rig? In most cases, this is due to the position of the graphic cards.

They are all hanging freely in open air. Several inches between each of the 4 cards.

I have 3x7850 +1x7970 working. But suspect I can get more kh.
Motherboard is "MSI Z77A-GD65 Gaming" 16GB RAM, Ivy Bridge i3 3225.
These are all off 1x to 16x adapters and strung up for cooling.
Temps are 63 82 56 61. The 82 is one of the 7850s, not the 7970!
I tried re-seating the heatsink. Seems like just a hot GPU chip.

Desktop runs off the 7850 in the 1x slot closest to the CPU.
Drawing 680w.  ltc mining about 362 kh on each 7850. But only 478 off the 7970.

[icebear888]

I have 2 x 7950's in the same chassis and the one also runs hotter than the other.

I dont know if its the CPU heat that might affect it.

[BigJim]

How much temperature difference are you seeing? Your issue is that they are in the chassis. If you get extender cables and hang your graphics cards in the air, like in many photos here, they should both run cooler and near the same temperature.

Or, if you keep them in the chassis, and swap them, one of the positions will run hotter. In my case, er situation, I believe this one card runs hot no matter where I position it.

[jmbinfo]

Are you underclocking?

[theface]

Are you using Afterburner?  You're monitoring temp, but what about CPU useage?  I have 4 7950s, and I have a similar problem.  They all run around 73 Celsius, but one consistently runs at 79-80.  Ive noticed via the CPU usage all 3 cards running at 73 C   jump between 99% useage to 64% usage.  They just toggle back and forth all day.  I was concerned at first, but it keeps the temp down, and I'm still get a good hash rate.  My problem card (4rth card) runs at 98 - 99% max useage all the time, thus, the temp stays pretty high.  Same setting as the other 3 card, but it won't toggle

[QueenB]

I have a same issue...

http://imgur.com/Lp7sFFb

[icebear888]

Maybe its because the furthest card is too far away from proper ventilation.

[ranlo]

I'm not 100% sure about this but I've read elsewhere that the main card (used for your video and such) will be hotter because the system is also utilizing it while the system's running. The other two are only being used for the mining.

[icebear888]

Ah, ok, that makes sense!!

Thanks

[Buffer Overflow]

Maybe the TIM is getting old on the hotter card and needs replacing.