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Topic: CGMiner Using CPU Instead of GPU? (Read 2995 times)

newbie
Activity: 27
Merit: 0
July 08, 2013, 08:21:05 AM
#1
Hi All,

I followed this guide:

http://rdmsnippets.com/2013/03/20/bitcoin-mining-with-ubuntu-12-04-tls-and-cgminer/

adjusting for the fact that I have a 64 bit system and 2xRadeon 6950 cards.  (I changed the CFLAGS for compile.)

Everything works smoothly, EXCEPT that CGMiner seems to be using my CPU and only one of my GPUs.

When I run ./cgminer -n, it shows both my 6950s.

However, in the output of the CGMiner, I see that GPU0 is getting 33k/344khs.  GPU1 is getting 399.2M/399.6Mhs.

In my previous setup with this computer (which I b0rk3d when I tried a beta driver) I was able to get roughly 375-400Mhs from both cards, to total around 750-800MHs on average.

*EDIT 1*
I have the GPUs overclocked with:
amdconfig --ode --adapter=all
amdconfig --odsc 900,300 --adapter=all
amdconfig --odcc
before running CGMiner.  This is how it was done with my previous setup that worked.
*EDIT 1*

It seems to me then that either:

1 - CGMiner is using the CPU instead of the first GPU and reporting that as a GPU.  Given that the temperature is running at 97.5C whereas the other GPU is running at 44.0C, this seems more likely to me.  I can feel the heat coming from one card and not the other, and the CPU is quite warm.
2 - My first card is somehow no longer working when it was just a few days ago under a different setup.  I consider this less likely.

*EDIT 2*
Using:
amdconfig --odgc --adapter=all
I can see that the GPU Load on Adapter 0 is 99%, and on Adapter 1 it is 0%.  This confirms my suspicions.
*EDIT 2*

*EDIT 3*
I've confirmed the second card is present in the X settings:
#cat /etc/X11/xorg.conf | grep -A 3 Section\ \"Device\"
shows two device sections
for PCI:2:0:0
and
for PCI:3:0:0
*EDIT 3*

Anyone have any ideas?  What settings can I change to force it to use both cards and not the CPU?  Or preferably all cards AND the CPU?  (Every kh counts!)
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