Quote from: Mikestang on March 05, 2015, 09:30:39 PM

Quote from: Phosphorous on February 03, 2015, 06:14:57 PM

Would be interested to see if anyone can get more than 2 to work together for more than a few hours.

Per my post two up (#630) my setup for a single U3 has been perfectly stable for like a week. I've been running it slightly overclocked, 775v and 237.5freq and it's been performing like a champ at about 58-60gh.

I bought two more U3s, however, I cannot get more than one of my 3 to run at the same time (I have so far only tried to get 2 going at the same time). I'm using cgminer 4.9.0 (4.9.1 won't see a U3 on my computer for some reason) with stock volt and freq while I try to get more than one going concurrently. I've tried launching cgminer with 2 plugged in at the same time and I get constant LIBUSB from both devices. If I unplug one the other runs just fine. If I launch cgminer with just one running it hums along perfectly, then I'll hotplug the second one in and instantly the LIBUSB errors start. I've tried with them both plugged into my powered USB 2.0 hub, and tried with one in the hub and the other in a separate USB port on my computer, but same results.

Is there something special that needs to be done to get multiple units running at the same time? Any of the three work by themselves. Thanks for suggestions.

Quote from: Mikestang on March 03, 2015, 06:15:15 AM

Now running in a powered 2.0 hub, seems to be happy for ~24 hours (knock on wood). Using a new power cable, too. This one is a molex 4-pin to barrel plug and has thicker wires than the pci-e to barrel plug I was using (2.5mm vs ~2.1mm).

I have since purchased a Multi TT USB 2.0 hub, but still cannot get more than one miner running at the same time. I hooked the USB hub up to my power supply, plugged in one U3 and it worked just fine. Plugged in the second and ERROR. Quit and restarted with them both plugged, more ERROR. They both hash together at about 30gh each (down from 59 alone), but with constants errors as below. So what else could it be? (I unplugged one USB toward the bottom, I think that's what the last 3 lines are starting to show)

Bitmain must have anticipated more than one of these being run from the same computer, what could be a resolution to this issue?