I'm mining ETH-HF on Dwarfpoof after a few weeks of down-time due to a cooked motherboard. Now that I'm back up and running with a fresh install of Ubuntu 15.04, I've been noticing that I'm getting a lot of "GPU gave incorrect result", "cannot connect" and a few other errors while mining. I've also noticed that even though I have FARM-RECHECK 300 in the command, which in the past led to each "hashing line" displayed on the monitor being displayed every .3 seconds or so at a very steady rate, now its a very ragged rate of .7 to 1.0 second, sometimes as slow as 6-7 seconds

My ethminer command is as follows:


are these issues because of the attacks on the network?

Or would it be the motherboard/processor being too slow ( Pentium Dual Core 3GHz with 4GB RAM , 2- R9 295X2 cards, Ubuntu 15.04 Desktop )

OR maybe I have something misconfigured?


Also, For some reason, I can mine using both cards, but trying to overclock using aticonfig or even checking the temperature of each of the 4 GPU cores, I can only control and/or access the temperature of the "default" GPU. The other 3 GPUs are inaccessible with the aticonfig command. Now this is a misconfiguration of something because the previous installation of ubuntu 15.04 mined just fine and I have full control over all the GPUs. ( That old installation was all kinds of mucked up with Monero and other coin mining junk - the reason for re-installing from scratch)

FYI - I followed this guide with an exception of using thelatest APP and Display Library downloaded from AMD, not the older stuff noted in the guide.

http://forum.ethereum.org/discussion/2695/frontier-mining-setup-notes-ubuntu-15-04-geth-v1-0-amd-ethminer

Any pointers to get this sorted out would be helpful

Thanks