Bitcoin Forum

Hi,

I have 5 Sapphire Dual-X R9 280x cards. When I use cgminer 3.7.2 in windows to produce scrrypt coins each of them produces about 540 KH/s. The same is true when I use a pre-compiled cgminer in Ubuntu 12.04, but, when I compile cgminer, it gets 730 KH/s. When I compile sgminer, it produces 540 KB/s.
So, I have a solution, to compile and use cgminer in Ubuntu. Yesterday, I installed Ubuntu 14.04 LTS. When I compile cgminer, it produces 540 KH/s. Anyone know the reason?

Try -g 2

Have a look here https://litecoin.info/Mining_hardware_comparison (https://litecoin.info/Mining_hardware_comparison) for suggested configs, but definitely looks like you should be getting around 750KH/s with those cards.

Anyway, I assume you would use the same config for cgminer on each Ubuntu release, so the problem must be elsewhere - made sure you are running the recommended versions of the AMD drivers and SDK on the new Ubuntu build? It sounds like you are not getting the overclock that you should be able to get with the 280X's.

I'm using this. Thanks anyway.

I'm using the correct configs just like the other people with the same cards. Thanks for the hints.

I've found something new. I have cgminer folder with good hashrates on a usb flash. I recompiled that on the new Ubuntu system, and guess what? It works fine (730KH/s). At the same time, when I use the other one, it produces 540 KH/s. It's weired. Also, sgminer has the same hashrate (540KH/s).

Another problem is that cgminer shows the information just like when I use -T at the end of the *.sh files. I can't monitor GPU information. I have 14.2 ATI VGA driver on the system and AMD-APP 2.9. I guess I should download 14.4.

Its been a while since I built a Linux rig so I dont have any specific suggestions, but the 540KH/s rate definitely indicates it isnt clocking the card as high as it should be. As you are using the same config as you get 730KH/sec with elsewhere it suggests driver problem to me, especially if you arent getting GPU stats.

I have seen people say that they had problems with the 14.x Catalyst drivers, so if 14.4 doesnt work maybe try going back to 13.1

Thank you for the response. I have been busy recently, sorry for the late answer.

I reinstalled Ubuntu and 14.04 drivers. Cgminer and sgminer now shows GPU info, but the problem was not solved.

I explain the solution for anyone who has encountered this issue. The problem is the kernel of the cgminer and sgminer (scryptxxxxTahitixxxxxx.bin file). I had a bin file in the nice working cgminer which makes it produce more hashrates. There is another one here:
http://www.reddit.com/r/dogemining/comments/1uj4uk/optimized_scrypt_kernel_for_hd7970_r9_280x/
which is a nice one. There is an instruction how to use it in cgminer on the website. To use it in sgminer just rename it from "scrypt130511Tahitiglg2tc8192w256l8.bin" to "ckolivasTahitiglg2tc8192w256l8.bin", backup your older bin file , if there is any, delete it and copy the new one in the sgminer folder.