I thought i would write this to help others when looking at what cards to buy for there Rig(s). Its a long post as i tend to rant… … but trust me… if you want to get max hash rate with minimal power consumption and use cheap GPU’s… keep reading…
I’m fairly new ( Dec 2017 ) to Rig building, in fact i’m still on my first which is only a month old so i dont have a huge amount of practical time on rig building but during the last month i have put a huge amount of time into tweaking, changing, trying settings and i think i have come up with great working solution.
For those that are interested, this is my post on building my rig which includes specs etc.
So, the AMD RX 580 GPU. I selected this card as its pretty cheap when compared to some of the Nvidea alternatives. I’m based in the UK and at the time of writing i can pick RX580’s up for around £220 ( inc VAT ) for a 4Gb model.
So 4Gb Cards… i can hear everyone yelling at me now saying thee the wrong cards… I chose 4Gb cards as initially this was an experiment to see what all teh fuss was about with mining… i never thought i would get so addicted and i wanted to keep my costs low. What a lot of people will tell you is to go with the 8Gb Cards… for the specific reason that they are not much more money but primarily because the DAG on ETH will soon be over 4Gb.
I disagree… not with needing 8Gb Cards but the DAG thing isn’t an issue… at the time of writing DAG is just over 2.5Gb… at the current rate it will not get over 4Gb until late 2019… by then i expect to have to replace my cards as they are running flat out.
However… one thing i have discovered is the RAM on an 8Gb card runs around 1000mhz faster than a 4Gb… This is VERY important as RAM speed = Hash Power… the more Hash Power you have the quicker the ETH is mined… the quicker the Eth is mined the quicker the dosh rolls in…
So Quick RAM = more Hash Power which is the real reason you need 8 Gb cards… but not because of DAG… although it will help increase the life time of the GPU…
Anyway… i digress… As i mentioned at the start of this post… i have spent a great deal of time changing and trying different settings which is you want to maximise any RIG… you should do the same… you invested in hardware… do the same with your time and config.
I now believe i have the best config for my RIG and thats what i want to pass onto the pub.
My rig now runs 7 Cards… which is 4 more that the original post… and yes… i am now addicted to mining … yes it does make me money… and yes… IT IS VERY COOL…
When i first got the 7 cards running, @ImaginaryPi you were right… anything above 4 is not without its huffing and puffing… the rig was running at 1340 watts… but i was running a hash rate of 219 Mh/s
I worked out that the core rig uses around 120 watts to run without any GPU’s mining so that was around 175 watts per card… i knew the cards used more power than an RX480 but even i thought that was high…
Sorry i should have mentioned… i only mine ETH and i use Claymore as my chosen software
So… after lots of reading of the Claymore config setting options and trying several of them i now have a rig needing 37% less power than its original config and i only reduced its output by 1 Mh/s
The rig now runs 3 x Gigabyte RX580’s 4Gb and 4 x Sapphire Nitro Plus OC 4Gb… the ONLY reason i have a mix is the Sapphires were bought later the the original kit and they were a bit cheaper…
They both have the same memory speed which is 1750 Mhz per Gb ( 7000 Mhz in total ). the Gigabytes CPU run at 1340 Mhz, the Sapphires as they are OverClock models run at 1411… out of the box.
NOTE - CPU speed is irrelevant… when choosing your card you going to under clock them anyway
My Rig is now running with a memory speed of 2130 Mhz for each card and 0.870 Volts and CPU of 1200mhz and 0.960 Volts… compare that to the original and it should make some sense.
I also run a custom BIOS… now this isn’t as scary as it sounds… simply save the original BIOS and then open it up in some software called Polaris and click on 1 click setting button… save it and apply it back to the GPU. If anyone isn’t sure on how to do this post a comment and I’ll write a more in depth set of instructions with links to the software apps you will need.
Why… well as i said earlier… faster memory = more Hash Power… and under volting everything - less power…
Depending on what model of cards you run you may need to / be able to alter some of these settings to suit. In essence play around with the settings i’m going to show you below and increasing or decreasing each one in values of 5… when claymore stops loading properly you have found the limit… crank it back a little and you have the sweet spot… Simples…
This is my Claymore config
EthDcrMiner64.exe -epool eu1.ethermine.org:4444 -ewal ETH WALLET ADDRESS -epsw x -mode 1 -etha 0 -cclock 1190 -mclock 2130 -mvddc 870 -cvddc 960 -tt -60 -fanmin 50 -platform 1 -powlim 20
If you want to know what each command does… download Claymore and open the Read.me file… its all listed in there
This shows Claymore in action… check out that Hash Rate
Reason i keep going on about the hash rate… most people only get around 29Mh/s … and use more power
This shows power consumption… Ignore everything other than current power as they all refer to old settings
NOTE - Invest in a TP Link powerSmart Plug… it has saved my bacon several times as it allows me to remote power off the plug if the rig crashes etc… obviously my rig is not at home…
Now these screeshots are from some software called GPUz which allows you to get get more in-depth info on your GPU’s
Power… for those that are interested… i pay £0.125 per KwH… my rig is running at around 973 watts per hour so £0.12 per per hour to run…£2.91 per day and £87.57 pr month
At 218 Mhs i generate 0.05 Eth every 34.8 hours… stats taken from Ethermine site… based on 870 hours per month thats 1 Eth every 25 days.
Eth is going up hence why its great to mine but based on current value which is 476 Bucks… or in English … £354… minus power costs thats £266 profit every 25 days
So for those that are asking is mining is profitable… your dam right it is
Hang on… whats about rig costs… what about them… it’s an investment… some people want there money back as soon as possible… well your wrong… you rig will last 3 years, maybe more… the right way to do it is to write off the rig cost over the 3 years… My rig with all 7 cards cost around £1800 plus VAT so if you have to pay VAT… thats £2160… spread over 3 years thats £60 a month…
So…after a month i have learned a huge amount… had great fun and now i’m making the monies…
whats next … well now i have overcome the huge power draw i encountered i am ordering 6 more RX580’s but 8Gb models this time. The 8Gb models will allow me to increase memory speed up to around 2250 i’m thinking. I’ll drop one of the Sapphires and run teh rig with 12 cards… which will maximise the main chassis… then who knows… all i know is the more rigs you have the mow monies you make…
Hope this helps both existing owners of RX580 rigs and those looking to getting into mining… feel free to comment.
PS… if you going to buy 8Gb RX580’s you need to check out the spec and ONLY buy the ones with 8000Mhz memory speed ( or 2000Mhz per Gb )… if you don’t you may as well save some pennies and buy the 4Gb models.