More information regarding the above that I just discovered:

i can confirm that most rejected shares happen on gtx1070ti and almost no rejected shares on gtx1070 ... this is only on 1.46 and 1.47. Somehow gtx1070ti has 5-10% rejected shares on 1.46 and 1.47 compared to almost 0% on 1.45.

gtx1070 have close to 0% rejected shares on all v1.45/46/47.

Importantly, I have 12 GPUs in every node, with an i3-7100 cpu. The nodes with gtx1070ti keep the CPU at 100% utilisation (on both 1.45 and 1.46/1.47) and the GPUs cannot handle anything else (even nvidia-smi fails, takes 5 minutes to show 1 line).

The nodes with gtx1070 has CPU utilisation at about 70%, and I can communicate with the GPUs while they are mining just fine (e.g. nvidia-smi is quick).

It seems that Gminer has an issue with gtx1070ti