This is a Linux issue trying to set up and mine with a new GPU. I recently put in an AMD Radeon HD7970 GPU in my desktop. Previously, I was running lasybear's sgminer on an AMD Kaveri A10-7850K APU. I was getting about 580 khash/s with that APU. Sgminer doesn't work with the new GPU installed. If I put my intensity over 16, I get the dreaded "GPU 0: invalid nonce: HW error". If I put the intensity to 16 or below, I get 100% rejected shares. I've tried switching my thread-concurrency between 4096 and 8192, and I've also tried taking off all of the parameters but "-o", "-u", "-p", and "-I". Also, when the shares are being rejected, the GPU is only running 350-400 khash/s. I'm using Ubuntu 14.04 64 bit, and I'm 99% sure it's a driver problem. I've spent hours trying to figure this out. I've installed version 2.7 of the APP SDK, which is recommended for 7970 GPU's. I've tried using the fglrx and fglrx-updates drivers in Ubuntu's "Additional Drivers" settings. They install fine, but sgminer has problems with them. I've also tried installing the Catalyst drivers directly from AMD's website. The 14.04 driver installed great but still had the sgminer problems. 12.8 wouldn't install because it was whining that there was no "/lib/modules/3.13.0-30-generic/build/include/linux/version.h" file. 12.6 wouldn't even download (Come on, AMD...). 12.4 installs great, but when I reboot the computer, I can't go to the desktop. As soon as I login, the xserver crashes and takes me back to the login menu. After searching through a bunch of online forums, the AMD drivers most people recommend for sgminer are 12.4 and 12.8. Neither of these are working for me. Whenever I install any of these drivers, I make sure that I run these commands: Code: sudo aticonfig --adapters=all --initial export DISPLAY=:0 sudo reboot Anyone have some direction for me? -----EDIT----- From the original post, it looks like people are having luck with the 14.6 Beta Catalyst driver. I never would've thought the beta driver would work better. :what: I'll give that a try later. I love Darkcoin, btw. Bitcoin's awesome, but it has a couple flaws that Darkcoin works out. Yeah, right now Bitcoin is way more popular, and the trend is for companies to adopt Bitcoin, but honestly, as more people learn about Darkcoin, they're going to choose it over Bitcoin. No one wants everyone to see where their money is going. I'm betting my money on Darkcoin, literally.