7x 1070 what psu you using could be anything dogey riser insufficient psu.... if your other rigs are running fine an it is just this one i would pull it apart start with one card and one riser install test then add another card keep doing that... that why you can test each riser / gpu and find the problem...
Hope that helped...
Regards
Nemo
P.S looking at the data you provided above:
GPU0 59C Sol/s: 331.3 Sol/W: 3.11 Avg: 331.1 I/s: 176.1 Sh: 0.00 . .
GPU1 61C Sol/s: 440.5 Sol/W: 3.95 Avg: 445.1 I/s: 238.0 Sh: 0.19 1.00 76
GPU2 55C Sol/s: 467.7 Sol/W: 4.14 Avg: 465.4 I/s: 248.7 Sh: 0.56 1.00 80
GPU3 58C Sol/s: 446.8 Sol/W: 3.99 Avg: 445.6 I/s: 238.1 Sh: 0.00 . .
GPU4 59C Sol/s: 455.9 Sol/W: 4.03 Avg: 454.3 I/s: 241.9 Sh: 0.00 . .
GPU5 57C Sol/s: 440.0 Sol/W: 3.96 Avg: 446.3 I/s: 238.5 Sh: 0.00 . .
> GPU6 63C Sol/s: 482.2 Sol/W: 3.58 Avg: 481.1 I/s: 256.2 Sh: 0.19 1.00 74
========== Sol/s: 3064.5 Sol/W: 3.82 Avg: 3068.9 I/s: 1637.7 Sh: 0.94 1.00 76
> GPU0 60C Sol/s: 335.7 Sol/W: 3.11 Avg: 331.4 I/s: 179.0 Sh: 0.00 . .
> GPU1 61C Sol/s: 438.4 Sol/W: 3.94 Avg: 444.7 I/s: 237.9 Sh: 0.35 1.00 79 +
> GPU2 55C Sol/s: 465.6 Sol/W: 4.14 Avg: 465.4 I/s: 248.7 Sh: 0.53 1.00 80
gpu_id 1 71 2 unspecified launch failure
gpu 1 unresponsive - check overclocking
gpu_id 5 66 3 unspecified launch failure
cudaMemcpy 1 failed
gpu 5 unresponsive - check overclocking
cudaMemcpy 1 failed
something seems to be wrong with GPU 0... Sol/s: 331.3 335.7 is over 100 sols short of what the other 6 1070's are doing may won't to start there...
you may won't to check your OC setting also...
i run my g1 Gaming 1070's at 70%tdp (120-125)watt +75 core +505mem
Nemo the gpu0 goes down 100 sols/s after I log into the rig. It gives that power to the display when I log into it:
========== Sol/s: 3163.5 Sol/W: 3.89 Avg: 3133.2 I/s: 1688.1 Sh: 3.30 1.00 78
> GPU4 60C Sol/s: 449.4 Sol/W: 4.00 Avg: 451.1 I/s: 241.9 Sh: 0.50 1.00 78
GPU1 61C Sol/s: 441.7 Sol/W: 3.93 Avg: 442.7 I/s: 237.6 Sh: 0.56 1.00 78
GPU2 56C Sol/s: 464.5 Sol/W: 4.09 Avg: 457.7 I/s: 246.6 Sh: 0.49 1.00 78
GPU5 58C Sol/s: 447.8 Sol/W: 3.95 Avg: 445.2 I/s: 238.2 Sh: 0.40 1.00 78
GPU3 59C Sol/s: 442.9 Sol/W: 3.93 Avg: 438.4 I/s: 236.0 Sh: 0.47 1.00 78
GPU0 63C Sol/s: 441.1 Sol/W: 3.77 Avg: 421.1 I/s: 233.9 Sh: 0.42 1.00 78
GPU6 64C Sol/s: 486.9 Sol/W: 3.55 Avg: 477.3 I/s: 255.8 Sh: 0.42 1.00 78
========== Sol/s: 3174.1 Sol/W: 3.89 Avg: 3133.5 I/s: 1690.0 Sh: 3.28 1.00 78
GPU4 60C Sol/s: 447.6 Sol/W: 4.00 Avg: 451.0 I/s: 241.8 Sh: 0.49 1.00 78
GPU1 61C Sol/s: 440.8 Sol/W: 3.93 Avg: 442.7 I/s: 237.5 Sh: 0.58 1.00 78 +
GPU2 56C Sol/s: 454.9 Sol/W: 4.09 Avg: 457.7 I/s: 245.6 Sh: 0.51 1.00 79 +
GPU5 58C Sol/s: 440.6 Sol/W: 3.95 Avg: 445.2 I/s: 238.4 Sh: 0.42 1.00 78 +
GPU3 59C Sol/s: 445.1 Sol/W: 3.93 Avg: 438.4 I/s: 235.0 Sh: 0.47 1.00 78
GPU6 64C Sol/s: 473.3 Sol/W: 3.55 Avg: 477.2 I/s: 256.0 Sh: 0.42 1.00 78
========== Sol/s: 3143.3 Sol/W: 3.89 Avg: 3133.4 I/s: 1688.2 Sh: 3.32 1.00 78
GPU0 63C Sol/s: 438.5 Sol/W: 3.77 Avg: 421.2 I/s: 234.1 Sh: 0.42 1.00 78
# server set difficulty to: 00009e842444b57508000000...
> GPU4 60C Sol/s: 456.1 Sol/W: 4.00 Avg: 451.1 I/s: 242.0 Sh: 0.49 1.00 78
> GPU1 61C Sol/s: 444.9 Sol/W: 3.93 Avg: 442.7 I/s: 237.0 Sh: 0.58 1.00 78
> GPU2 56C Sol/s: 454.4 Sol/W: 4.08 Avg: 457.7 I/s: 244.3 Sh: 0.51 1.00 79
> GPU5 58C Sol/s: 447.1 Sol/W: 3.95 Avg: 445.2 I/s: 237.3 Sh: 0.42 1.00 78
> GPU3 59C Sol/s: 446.8 Sol/W: 3.93 Avg: 438.5 I/s: 234.5 Sh: 0.46 1.00 78
> GPU0 62C Sol/s: 382.5 Sol/W: 3.77 Avg: 420.9 I/s: 207.6 Sh: 0.42 1.00 78
> GPU6 64C Sol/s: 481.5 Sol/W: 3.55 Avg: 477.3 I/s: 255.3 Sh: 0.42 1.00 78
========== Sol/s: 3169.3 Sol/W: 3.89 Avg: 3133.7 I/s: 1684.5 Sh: 3.30 1.00 78
I dont think there is a hardware issue as there have been times it ran for over 24 hours without any issues. Its going on almost 5 hours now and no errors dished out. Fingers crossed.