Quote from: Epoch on July 30, 2014, 01:13:06 PM

Quote from: iglasses on July 30, 2014, 12:59:33 PM

Quote from: not.you on July 30, 2014, 12:46:28 PM

Quote from: FlensGold on July 30, 2014, 11:14:41 AM

Does anyone have an idea what can lead to this hashrate?

All chips seem to be fine. It is powered by a 1600W PSU (all 4 PCIe Cables connected), but it is only ~half of the promised hashrate.
Latest firmware is also installed...
Kind regards

Try a reboot.

That's an odd temperature difference between the two chains.

If you look at the HW (hardware errors) column, the number there is huge for the 2-day mining period. One of the chains (likely the low-temperature one) is having trouble. I have an S3 that behaves similarly and gets similar numbers; the hashrate is just slightly above 1/2 nominal (meaning 230-250).

If you reboot it, you may find that it hashes fine for a few minutes then one of the chains will start acting up again and your hashrate will drop. When this happens you'll see the HW number start going up. For my unit, I took off the case and removed the 2 externally-facing heatsinks to see if it was making good contact with the chips. It seemed fine, but I re-applied thermal compound and re-installed the heatsinks. This didn't make any difference.

What I ended up doing is UNDERCLOCKING the unit. Try 212, and lower if you have to. It can help if you power the unit down completely for a few minutes to let it cool down. I got my unit running at 395GH/s for about a day before HW errors started spiking again. I underclocked it further and it has been stable now for a few days.

YMMV.

I'm not sure I would call that HW error number huge... it's 0.034%. It's certainly larger than what I experience on my S3s, which give me about 0.0017%. The WU number is very telling, though. You're getting 3525 and you should be somewhere between 6100 and 6200 at stock clocks. Also, the extremely low temperature of chain one is an indication that something funky is happening there. If you reboot it from the web console, does it come right back up and show all ASICs as "o" status on both chains? If yes, then there's a power problem and the ASICs on that first chain aren't getting fed enough to hash at the specified clock rate. Another question: if you power down the unit completely for about 5 minutes, then start it back up again, does it report proper hash rates, but then drops over time? This would also point to a problem most likely in the DC/DC component. What happens if you try to clock it lower (like 212.5 or even 200)?

Finally, I'd open a support ticket with Bitmain.