Mining Rig Issues Gigabyte GTX1060 6Gb G1 Gaming

[bobster316]

 I have a mining rig with 6 x Gigabyte GTX 1060 6GB G1 Gaming not sure if they are ver1 or ver2.

When mining using simple mining i have noticed that two of the GPU's have a lower hash rate than the others.

4 running at approx 20H/s and 2 at 15.5MH/s

Any ideas?

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