This follows on from Part 5 of my step by step guide on how to build a 6 GPU Mining rig and explains how to flash your GPU bios. You should now have a working miner running Nicehash Legacy, all be it with only one graphics card and on stock settings.
Now it’s time to flash the bios on our first card to see if we can increase our mining performance and reduce our power usage.
You can download various pieces of software which will allow you to adjust your cards memory timings, voltage and core speed manually, but that is out side the scope of this beginners guide.
We are going to use pre-made roms that other people have created for similar cards and simply flash our card to the same settings.
There is an excellent guide on how to flash your GPU here and various warnings against flashing in Windows!
However, that said I have flashed at least 50 cards in windows using ATI Winflash and have never had an issue. If you want to follow the longer method above great, but for this guide I’m going to use ATI Winflash.
!!! Warning flashing your cards will almost certainly void your GPU warranty and could brick your cards. In addition running your cards 24/7 at overclocked setting may cause them to fail quicker than with normal use. Proceed at your own risk!!!
Assuming you are happy to go ahead you now need to download ATI Winflash to your desktop:-
If your card has a switch to change between stock and overclock settings, make sure it is switched to overclock. The image below shows the Powercolor Radeon RX580 8gb card. The stock setting is your fail safe if anything goes wrong with the flash.
If it’s not on “overclock” then turn off your mining rigs power, switch it to overclock and boot your mining rig up again.
Finding a GPU Rom
Now open up GPUZ which we downloaded in part 5 and make a note of the memory type your card has, your default clock and memory clock speeds. Each card can have a different memory type, even if you purchased the exact same card from the same supplier.
Now fire up ATI Winflash (you must run as administrator).
Once on the dashboard click “save” to take a backup of the current bios rom settings. Make sure you save the rom file name with some reference to the card. i.e. if you have six cards connected to your rig, you may want to number them 1 to 6 and make reference to this on the BIOS roms file name.
Next you need to search for a rom for your card and memory type on anorak.tech. The rom you are looking for needs to be the exact same model and memory as your card. Generally searching for a mining rom/powersave rom should find you what you want.
The roms I used for my cards were as follows (you need to login to Anorak.tech here before clicking on the links):-
Save the rom to your desktop ready to flash your card.
Flash your GPU BIOS
Now that you have downloaded your rom you can fire up ATI Winflash again. I suggest closing down all other programs and disconnecting your mining rig from the internet first.
Once open you need to click on the load image button and select the new rom from your desktop.
After it has loaded you then click “program” and hold your breath!
Your screen will freeze for several seconds, just be patient and let it do it’s thing. Once it’s finished you will be prompted to restart your rig.
Now open up GPUZ again and check your default clock and memory clock speeds. These should have been adjusted from before.
In my case my GPU clock has been dropped to 1,200Mhz and my memory has been increased to 2,150Mhz.
Nicehash Miner Benchmark
Now it’s time to power up Nicehash again. This time we are going to run all the benchmarks on the precise setting. Before we do you need to navigate to the settings page again and make sure “use 3rd party miners” is ticked. Click save and exit.
Now click benchmark and this time select all the algorithms and choose precise method. Click start and Nicehash will now benchmark your card against every miner. This may take 30 minutes or so.
Once it’s finished you can start mining again. Nicehash will automatically select the most profitable miner. In my case DaggerHashimoto (Claymore) has started running and you can see my hash rate is 30.5Mh/s. Your hash rate should have increased to between 29Mh/s and 32Mh/s.
Your actual speed will differ depending on the memory your card uses. In fact even cards with the same memory will be slightly different due to differences in the manufacturing processes of your GPU processor and memory.
You can now open GPUZ to check the power draw and temps of your card. You can see my RX580 is now pulling 112.9W, running at a temperate of 69C or 156F and a fan speed of 34%. Whilst you can crank the fan speeds up to get cooler temps, I tend to leave them on auto provided your temps stay below 75C or 167F.
That’s it for Part 6. In part 7 we will look at connecting up and flashing your renaming 5 cards.