Hello

Odd numbered GPU's (GPU 1, 3, 5, 7) has lower hashrate than even numbered ones.

setup is like that;

9x Gigabyte Gtx 1080 Windforce (Coreclock +160, Memory Clock +800, Power limit 150)
Biostar BTCPro for 12 GPU
PSU: 750 watt FSP or Corsair supply for each 3 GPU

OS: Simplemining
Miner: SGMiner, CCMiner (Both of them has same problem)
Algo: X16R (I experienced this problem with Lyra2Rev2 also )

P.S I tried different PCIE slots and different risers already.

Best Regards
//Mert