http://www.prweb.com/releases/2014/09/prweb12165371.htm

Another correlation with the Bitcoin price and the Obamas, similar to Obama says the US will attack Syria, Bitcoin value rises to new heights

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I've got 92 BFL Chip Credits for sale.
I accept Bitcoin only as payment, and in order to protect YOU, I want to use escrow.

If you're planning on buying BFL chips, you no doubt want to get them cheaper.

PM me if you're interested; I'm asking for BTC11.

Thanks,

Hi all,

I'm wondering if anyone has had any luck getting the QRCode plugin to work on OSX?

I've made very little progress on this front.
The QRCode plugin depends on zbar being installed.
zbar depends on ImageMagick+ to be installed
...and ImageMagick+ depends on video4linux to be installed.

I can't seem to find video4linux for OSX and fear it may not even exist, making this awesome plugin inaccessible for OSX users.

Have any of you tried tackling this? If so, what progress did you make?

Looking to sell an AppleTV (3rd Generation) for Bitcoin.

I can offer it at slightly less than retail price. (It's available for $99USD+tax, I will accept the equivalent of $85USD in Bitcoin)

Let me know if interested!

[I've come to accept that the 2nd GPU on my 6990 card just hashes erratically when the 1st one is in use.]

So in the hopes that my findings will help others, I've decided to start this post and document all of the little glitches/oddities I've encountered while preparing my mining rigs.
Aside from the noble goal of helping others, I also hope a more knowledgeable miner can recognize these oddities and either provide confirmation that "Yeah - that's weird but normal" or perhaps even point me in the right direction on how to resolve it.

Before I begin, here's a simplified list of my setup for your comparison

• LinuxCoin 0.2a running persistent from a USB key
• Sapphire ATI 6990 video card

And here are the oddities I've found and learned about:

• Hashing:
  
  • When GPU0 is hashing alone, it hashes at a constant, steady pace. For the purposes of this example, let's say 350000 kh/s
  • When GPU1 is hashing alone, it also has a constant steady rate of 350000kh/s. (example value)
  • When GPU0 and GPU1 are hashing at the same time, GPU0 is a steady 350000kh/s while GPU1 has an erratic rate that jumps between 350000 and 200000kh/s.
  • The moment I'd kill GPU0, GPU1 would become stable at 350000kh/s. When I'd resume GPU0, GPU1 would become erratic again
  • The moment I'd kill GPU1, GPU0 would continue hashing stably at 350000kh/s. When I'd restart GPU1, GPU1 would be erratic
    
  • My first thought was temperature of GPU1 - perhaps it was being throttled for overheating? Nope. GPU1 temp is about 5 degrees cooler than GPU0 temp.
  • My second thought was power - with two 8pin PCIE inputs on the card, one was being fed by a 6-8 adapter. Nope, when the 2nd power lead was replaced with another dedicated 8pin PCIE, the same erratic hashing was observed
  I've come to accept that the 2nd GPU on my 6990 card just hashes erratically when the 1st one is in use.
• Overclocking with aticonfig:
  
  • When I attempt to use aticonfig to set clocks directly (within the peak limits) it does not work
  • When I use AMDOverdriveCtrl to set clocks (within the peak limits), it works great
  • If I launch AMDOverdriveCtrl and then shut it down, and THEN use aticonfig to set clocks, it works like a charm
  • I guess AMDODC does something behind-the-scenes that makes aticonfig work?
  I've come to accept that you just need to AMDODC first before aticonfig-ing.
• Overclocking GPU and Underclocking Memory:
  
  • If I try to overclock the GPU too high, it may hash fine for 5mins, 10mins, or even 2hrs until eventually the system freezes/halts
  • Overclocking a little bit doesn't produce any system halts!
  • When overclocking a little bit, you can have the Memory underclocked by more than 100MHz when compared with the GPU clock. (I had a 135MHz spread that worked great)
  • When overclocking a lot, you must keep the memory underclocked no more than 100MHz when compared with the GPU clock
  • If I attempt to overclock/underclock things that the 6990 doesn't like, it won't give me an error or tell me it failed. It'll silently reset the clocks to factory defaults. I need to check the clocks after setting them to see if the card took the settings.
  • I have read (but haven't tried) that editing the GPU BIOS with RBE allows more reliable overclocking for other cards, however from what I am able to find, 6990 users report that only the voltage can be changed with RBE?
  I've come to accept that overclocking/underclocking a 6990 has very little impact since you can't overclock the GPU too much without freezes, and you can't underclock the memory too much without it being undone. I wish there was a way to adjust the clocks in Linux more reliably.
• Monitoring and remote management:
  
  • If you try to run aticonfig or launch a miner over SSH, it won't work because the ssh session's "display" doesn't have a GPU
  • If you have a GNU screen session open on the machine, you can resume this session over SSH and have full control of everything that screen session had when it was first initialized
  I've come to accept that you need to start a GNU screen session first and then do everything inside it if you want to be able to remotely manage things
• Performance
  
  • My original goal was to have a headless, windowless environment for mining. Everything would exist in CLI land, and no window manager would be necessary. No KDE, no gnome, no "startx." I assumed it would use less GPU power to display a CLI environment than a window manager environment.
  • That doesn't seem possible without perhaps modifying drivers and other low-level things to make the GPUs available to command-line programs
  I've come to accept that you need to use a window manager in Linux in order to access the GPUs

I hope these nuggets of acceptance help some of you out there.
If you are able to provide any insight or assistance into these oddities, I'd be very happy to learn something new!

--TE