Have I damaged my RX480

[Ancalagon44]

Hey everyone,

So I have an RX480 that I use for mining ETH and DCR using Claymore's dual miner.

Everything was going fine, I had an ETH hash rate of about 24 MH/s. I have an RX480 4GB and I had overclocked the memory slightly to 1900Mhz (from 1750).

I read that some 480 owners had undervolted their cards for better performance and power consumption. I decided to try it out. I went to AMD Wattman, changed the voltage setting from automatic to manual, and entered 1050mV into the two right hand side entries (the highest power states). The default values are 1093 and 1131.

I also increased the memory overclock slightly to 1950Mhz. I know that RX480 8GB cards run at 2000Mhz, I was hoping that mine could one day do 2000Mhz.

So it didn't immediately crash or anything, and I left it to mine. I came back a few hours later, and saw that apparently the display driver had crashed because there was no picture on my screen. I reset it and went back to the previous settings of automatic voltage control and 1900Mhz memory clock (which was stable for days on end with mining, like literally 2 weeks).

But here is the thing now - it doesn't crash, but I can't get the hash rate that I used to get. As soon as I increase the memory clock above 1750 - even to 1760 - my hashrate drops from 22 to 19. Memory overclocks of 1900 don't crash it, they just make it run slower. GPU-Z confirms that my memory is set to that speed, but it still slows the miner down. 1750 is the fastest setting for it, considerably faster even than 1760.

No instability though. I haven't tried a game yet so I haven't noticed any artifacts, although I'll do that tonight.

Any ideas? Have I damaged it somehow? Is that possible?

 

[Shmee]

I doubt the card is damaged, but perhaps is not completely stable at higher settings, hence the lower hashrates. Something you could also try, in addition to games as you stated, would be another miner. Also, try restarting the computer to see if that helps, if it has not been restarted in a while.

 

[Ancalagon44]

I think I fixed it.

I tried restarting the computer, multiple times. I tried a different miner. I even changed the overclocking setting, and then restarted, but that didn't help either.

I was mining when I noticed that the GPU clockspeed was 750Mhz. After a fresh restart. So, I decided to reset the AMD Wattman config back to defaults - there is a Reset button at the top right. Immediately the hashrate jumped up.

After that, I was able to overclock the memory back up to 1900Mhz and get the hashrate of 24 that I used to get. So, it looks like some setting got changed that broke it, and I couldn't change it back. At least, maybe I didn't notice not.

I'll leave it on 1900 Mhz for a while.