Litecoin Mining – Sapphire Radeon R9 280X Sweet Spot for 760KHash/sec
Keeping up with the R9 280X cards, this time i will share my configurations for the Sapphire R9 280X card. Previously, i have mentioned that CGMiner version 3.7.2 with the latest drivers would give you a higher hashrate as the R9 cards would be classified properly as 200 series cards. With the updated driver, R9 280X cards would run much cooler and most could reach above 700KHash/sec.
After some tweaking, I have managed to get the Sapphire R9 280X to produce around 760KHash/sec per card. Let us look at how to configure the PowerColor R9 280X for higher hashrate and possibly lower power consumption.
How to optimize Sapphire R9 280X for Litecoin mining
Undervolting
Since the 280X is a rebranded 7970, it is possible to undervolt the cards using the VBE7 method that i have outlined in the previous tutorial: How to modify video BIOS to undervolt GPU in Linux. There is an additional step before you attempt to undervolt the BIOS though.
Similar to some other R9 280X cards, my Sapphire is voltage locked. If you are experiencing the same issue as mine, you can try to update with this BIOS and use VBE7 to load this instead:
password: rumorscity
After flashing the BIOS, my Sapphire card run completely stable at 1100mV, so if you are using my undervolting method, simply replace the 1081mV that i have recommended with 1100mV.
CGMiner settings
For this test, i am using BAMT version 1.1 with the latest AMD Catalyst drivers installed and CGMiner 3.7.2. You may learn more about setting up BAMT in my tutorial: Litecoin BAMT version 1.1 – Easy USB Linux mining distro.
I get the best result from this CGMiner configuration:
-g 2 -w 256 -I 13 --lookup-gap 2 --thread-concurrency 8192 --gpu-engine 1090 --gpu-memclock 1500
This configuration gets me around 760KHash/sec on each card with a low reject ratio. Most brands of R9 280X can reach hashrate of above 700KHash/sec. I will try to spend some time and post the configurations for each and every R9 280X i can get my hands on.
Update 8/1 – Found a new BIOS for the Sapphire R9 280X card, where after undervolting, it is possible to tweak the hashrate from 740KHash/sec to 760KHash/sec. The images have been updated with the new configuration and hashrate.
Did you ever burn any powered riser cables? I think I had overwhelmed the power being drawn through a few powered risers. From everything I can find online, it seems that the fans might be running at to high a RPM. I think the fans are pushing 100% most of the time, which would explain it. I’m just looking for more info thanks. Whats your cgminer setting set on for fans? do you clock them down to keep them from burning out?
Most of the time, i set my fan at 60-90. Sometimes even 100. But i didn’t use any powered risers. Haven’t had any problem so far.
So your not using powered risers at all? How many R9 280x cards per motherboard maximum have you ran at once? And what motherboard are you running.
I have 3 to 4 GPUs on each rig. All my risers are non-powered.
Gigabyte Z87X-D3H : 4 GPU
Gigabyte H87-D3H : 3 GPU
ok thanks for the info. I saw this http://www.evga.com/articles/00600/ looks like its usually for overclockers but it rises the amps/levels voltage on the ports.
will this bios work on a “Sapphire Radeon
Dual-X R9 280X 3GB 11221-00-20G” card? i have 3 and 2 of my voltages are locked at 1.175 and the other is at 1.225, really strange since they were all purchased together
This vBIOS is for Sapphire Toxic R9 280X. You can try to search the vBIOS for your model at techpowerup http://www.techpowerup.com/vgabios/147311/sapphire-r9280x-3072-130913.html
Hi I have 2x R9 280x also I am using -gpuengine 1080 only. but after been running for like half hour, there will be a message pop up saying the program has encounter problem and I can only close it.
I am mining on windows with CG miner 3.7.2
catalsyt driver 13.1 beta v9.5
sdk 2.7
it seems other miner do not have this problem.
any help will be appreciated.
You can try to update the drivers. But i am more familiar with Linux as i am using BAMT.
hi thanks for the prompt reply, I guess the gpuengine is too high on the primary. now I use 1030, 1080 it is smooth
Great to hear that. I agree that some cards have a slight difference on configurations. One of my four Gigabyte cards goes smoother on a lower clock speed. So you can always take my configuration as a base and tweak further from there.
Hey.
I’ve got the Gigabyte R9 280X Rev2, and so far only achieving 690 and 711 on my two cards, but your configs were the ones helping me from a meager <600, so thanks !
Have you measured/estimated how many watts your various 280Xs draw?
And do only recommend 280X for litecoin mining, or how does it stack up against R9 290(X)?
I'm trying to figure if the initial extra cost will be made back in khash/w efficiency and needing less PCIe-slots for the same totalt hash?
Thanks for any thoughts and experiences!
Many thanks for this guide. I am finally able to get stable 760khash on my rig using BAMT 1.2 and 2x R9 280 toxic.Was initially struggling between 500-600khash.