After the system crashed when I tried 4.8GHz at 1.375V, I went back to 4.4GHz at 1.370 and ran Prime95 for 12hrs+ and ran BOINC for a day or two. I then bumped it up to 4.6GHz at 1.370V and ran Prime95 for 12 hrs+ and BOINC for several days.
I did this while I was waiting for some new fittings to fix the loop between the CPU block and the Koolance blocks for the RIVE MB.
The problem I had was that there was a height difference of about 7-8mm between the CPU block and the MB blocks. There is not much distance between these connections and the heigth difference made for a risky sharp bend for the tubing. I am surprized it took me so long to find a solution. I kept looking for a way to simply add a 8mm spacer. I could not find one. But, Bitspower makes spacers that are 15mm, 20mm, etc up 40mm. I finnally realized that I could put a 15mm on the tall port and then whatever size spacer needed on the low port and I could always end up with +/- 2.5mm difference in height. This height difference is small enough for the short distance I have to go to allow for acceptable bends in the tubing.
Here is a photo of 15mm spacers on the high ports (the CPU block) and 20mm spacers on the low ports (the MB blocks):
Here is a view from a higher angle:
And an overall shot of the whole MB tray before I put back in its home:
I will try to get a shot of this installed in the STH10 case after the leak testing is complete.
My next task is to start the power cable sleeving. I intend to make custom cables to fit exactly inside this case. I'm still thinking about how to route all the power cables. I need to install the second PSU and distribute the total load across both PSU's. I intend to have 4 GPUs in this rig when it's all done.
Right now my think is that I will wait until the "Big Kepler" EVGA Classified cards are available. I might be waiting awhile for those...
I might have to buy a GTX680 Classified in the mean time. I know the GXT680 is not the best at GPU compute, but I thin kit is slightly better than the GTX580 for GPU compute (the primary use for this rig). I will continue researching the capabilities of the Keplers.