Does anyone know if it's safe to overclock the new Antminers with the onboard 6-pin PCI-E power connectors when only powering the device with the PCI-E connectors? (nothing in the screw terminals)
I thought the PCI-E power cables felt kind of warm when running on stock clock but it could have just been heat from the unit itself so I want get another opinion. I'm considering a nice modest 375 overclock.
I guess this question could also be, "is it safe to draw 400-500 W from two 6-pin PCI-E power cables?"
It is safe, I would say over 300W per PCI cable is where you run a risk (look at the bitfury threads, where a full rig can draw up to 800W if overclocked, and there are a few cases of burnt-out PCI cables (most of these though were the 2-headed cables, rather than 2 seperate leads).
As long as the cables are good quality and fairly thick, 200-300W each shouldnt be an issue. One of my antminers is powered by a single 4-pin ATX lead (2x12V,2xGND) to each blade with no issue. However, if your cables have zipties or are in a mesh wrap, it could cause a lot of warmth to concentrate in some areas rather than radiating away or being blown away by a fan. If your cables get warm, just direct some airflow over them and they will quickly return to room temps
Thanks for the info- it seems that some of the cables are just getting warm near the PSU connector but the rest of the cable feels fine. I'll keep an eye on it but it wasn't warm enough to cause concern.
I'm running two miners on a 1000w PSU and measured ~685w at the wall with no overclock, ~725w at the wall at 375M, and ~780w at the wall at 400M. I was expecting a lot higher based on the other posts in this topic; maybe I didn't do something right? (I edited /etc/config/asic-freq and power cycled the miners)
The web interface on most of my Antminers is showing GH/S(avg) to be between 195-203 GH/s and temps are between 42-47.