RX 570 / 580 dropping hashrate from 27 to 18MH

[DS313]

I've an issue I was unable to solve after spending days searching and investigating.

I’ve modded few cards MSI / Gigabyte, 570/580.

Very basic mod - timings shifting, and undervolting to 950mV.

All of them of them exhibit the same pattern – start mining high speed 27 - 28MH, and then – few minutes to few hours – drop performance to about 18-20MH.
https://i.imgur.com/VslBkvv.jpg
Tried MSI 570 and 580, Gigabit 570 – all have the same pattern.

Different cards with Samsung or Hynix, different motherboards, different risers, quality power supply (EVGA 1300, tried different models), single or multiple cards.  different driver versions. Same behavior. http://

Use claymore in eth - only mining through nicehash.

Thanks a lot for any hints!

[leonix007]

I've an issue I was unable to solve after spending days searching and investigating.

I’ve modded few cards MSI / Gigabyte, 570/580.

Very basic mod - timings shifting, and undervolting to 950mV.

All of them of them exhibit the same pattern – start mining high speed 27 - 28MH, and then – few minutes to few hours – drop performance to about 18-20MH.

Tried MSI 570 and 580, Gigabit 570 – all have the same pattern.

Different cards with Samsung or Hynix, different motherboards, different risers, quality power supply (EVGA 1300, tried different models), single or multiple cards.  different driver versions. Same behavior.

Use claymore in eth - only mining through nicehash.

Thanks a lot for any hints!

Are you using Adrenalin Drivers, Check the settings if Compute mode toggle is enabled also Have you play with your clock settings in MSI AB or Overdriven Tool? there are sweet spots on every card. my config is

2100 Mem
1100 Core

Sometimes I glance at 22mh/s however it goes back again to 29+ mh/s so I dont bother

see this thread for other users clocks on their RX 570/580

https://bitcointalk.org/index.php?topic=1874892.0

[DS313]

Thank you, yes this happens with the latest drivers, with Compute mode selected. 

Thank you for the link, will check it out.