I removed all but 8 amd gpu's and installed the latest blockchain driver and the hashrate went back up to 30-32 per gpu. This limits me to 8 amd gpu's on the rig which sucks. I am thinking the problem must be an issue with the dag size. This would explain why Pirl is getting full speed while Ethereum isn't. I boosted the virtual memory to 64 gb and figured that would be enough to take care of any of the problems the dag size might present by not using the blockchain drivers(didn't fix the problem though).

Maybe I will try the 17.11.4 driver and see if it will work properly on those drivers and allow me to go beyond 8 amd gpu's while still hitting 30-32 mh/s.

I have a rig running windows 10 made up of 4 rx 580's, 5 rx 570's(all modded for max hashrate) and 4 gtx 1060's on the asrock h110, 8 gb ram. When I mine the Pirl currency using claymore I get between 30 and 32 mh/s per amd gpu. When I mine Ethereum using claymore(with exact same settings) for some reason I get 22-24 mh/s per amd gpu(about 8 mh/s lower per card than it should be). The Nvidia gpu's give me the same hashrate for both Pirl and Ethereum.

I have tried mining with 1 amd gpu at a time but still get 22-24 mh/s. I thought it might be that I didn't have enough virtual memory so I bumped it up to 64 gb but still no change. I have tried both crimson 11.1 and adrenaline 12.1 amd drivers(currently using newest amd driver adrenaline 12.1). The rig is stable mining Ethereum running all 13 gpu's hitting 300 mh/s at 1500 watts from the wall. Mining Pirl with all 13 gpu's gives me 370 mh/s at 1650 watts from the wall. A power usage difference of about 150 watts

For some reason it seems like the amd gpu's are being throttled when mining Ethereum. Causing them to hit a lower hash rate and use less power. I haven't changed any settings in Claymore to over/underclock the gpu's so its really odd that this would be happening. If I mine Ethereum using the exact same settings that I use for mining Pirl I still get the 8 mhs difference per card even though both are running using the same EthDcrMiner64.exe.

Anybody experienced/experiencing a similar issue? I have a second smaller rig with 2 rx 580's and it is getting 31 mh's per card mining Ethereum with claymore using the same settings as the rig thats only getting 22-24. This problem has me totally confused.

Any ideas or thoughts would be a big help.