Can I do it with wattman?
This article says I need to turn clock memory to 9 GHz. However, it doesn't tell me how
Moving to overclocking, the only thing we need to do is increase the video memory to the maximum and in this case this means 9 GHz (the card might be able to handle more, but the overclocking software or the driver is apparently capped at 9 GHz max). With the video memory at 9 GHz the RX 480 is capable of delivering about 28 MHS hashrate for mining Ethereum. It is highly possible that even higher hashrate could be achieved if you manage to get past the 9 GHz limit for the video memory, but for the moment AMD’s WattMan software or the Asus tool that we used do not currently allow for more. With the memory overclocked the power usage is increased with just about 7-8 Watt at the wall, so definitely worth overclocking it for mining Ethereum. We were a bit disappointed by the lack of overclockability headroom of the GPU that was able to get just about 1340 MHz with the stock voltage. Of course no point in overclocking it for Ethereum mining, in fact you might want to actually downclock it to get better power efficiency if mining only Ethereum.
http://cryptomining-blog.com/8033-testing-the-amd-radeon-rx-480-for-ethereum-mining/2 things are required to achieve ~30mh on an RX480
- Edit Memory Timings in Bios
- OC Memory to 2150
If you OC the memory to 2150mhz without editing the timings you'll get yourself about 26-28MH
If you OC the memory to 2250mhz (9000 effective) you'll be able to achieve close to the same thing but many cards will not OC the memory this high.
It's better/safer to go with a lower clock speed and tighter memory timings in bios. It uses less power as well.
In Summary, You need to mod the bios, have someone mod your bios or find someone who has already modded the bios on the exact card that you have and is making it available for download.
