I use 3 Vga
GPU0 4GB Sapphire R9 290x
GPU2 2GB Asus R9 270
GPU2 4GB MSI RX 480 X Gaming
First run (no mod) GPU2 : 24Mh+ : Core clock 1275, Mem Clock 2000
Second run (modded) GPU2 : 30Mh : Same clocks, so: 1175, 2080

Greetings!
Is your card Hynix of Samsung or some other memory.
Unfortunately I have hynix. (Just bought those 6 cards) with 1500 strap I cant use anything more than 1950/1000 for memory. Any help will be great. Cheers
I know of people running the 1500 strap timings copied over via Polaris editor and getting 175sols.
Are you changing the memory individually or are all six GPUs linked when you change the frequency?
I'd look at the asic quality of my cards and see if one of the cards is holding back the rest.
1950 memory is still great, I honestly only seen a 5% improvement at 2200 vs 2000 on my Msi 480 8gb.
What were your results prior to the strap?