Try to set -gt for rig 2 manually the same as on rig 1.
Maybe the problem is that on rig 2 cards with worster memory than on rig 1...
Cards from the same batch. I used the Claymore for more than a year, until it stopped working, there was no such problem and the speed was 30Mh+
After set manual -gt on rig2, speed has not changed in any way
Cards the same all? It's very strange... Rig 2 take more power but speed is lower... Windows and drivers the same too? Video bioses the same on rig 2?
Rig1 and Rig2 use one driver - "main OpenCL driver version: 19.12.1". Windows 10. The bios has not changed anywhere.
There are differences in RAM, on Rig1 4Gb, on Rig2 8Gb.
So rig2 have different type of memory. That's the problem. You need find best straps for youre type of memory and modify vbioses or apply better straps with some prorgam like AMD memory tweak tool.
Did you tried -mt 2?
I did not write correctly, differ in RAM in the system, how can this affect?
With -mt2 Rig1 show lower speed on some cards:
GPUs power: 457.5 W
2020.10.11:19:37:26.524: main Eth speed: 152.400 MH/s, shares: 7/0/0, time: 0:02
2020.10.11:19:37:26.524: main GPUs: 1: 20.972 MH/s (1) 2: 21.215 MH/s (0) 3: 29.920 MH/s (1) 4: 29.944 MH/s (2) 5: 20.414 MH/s (2) 6: 29.934 MH/s (1)
rig2 speed don't change:
GPUs power: 519.1 W
2020.10.11:19:34:58.227: main Eth speed: 157.024 MH/s, shares: 29/0/0, time: 0:10
2020.10.11:19:34:58.227: main GPUs: 1: 26.080 MH/s (8) 2: 26.170 MH/s (3) 3: 26.232 MH/s (4) 4: 26.072 MH/s (7) 5: 26.235 MH/s (2) 6: 26.235 MH/s (5)