Quote from: davebodger on February 20, 2014, 02:02:41 PM

Quote from: TRN1062 on February 20, 2014, 06:18:04 AM

Hi,
I have a problem maybe someone here can help me with. I am running 9 Antminer u1's and I am now sure my issues should not be power related as I have 8 of them running on two separate hubs (5 , 3) I have powered the hubs using a 12V 30A regulated power supply. I have run 5 of these ants on the 9 port hub I now have the 5 on before and they ran for days straight with no issues cranking out 2ghs each. I know one of my ants throws HW errors at the 2gh clock rate so that was running on a different PC at 1.8ghs so at that time I was running just under 12ghs. I have since added the other 3 Ants and now I am having troubles I know the 9 port hub can run the 5 ants and the artec breeze fan without issues and I know the other (7port) hub can run the other 3 without issue but yet if I run both hubs on the same computer the rig keeps shutting down. It will run fine for a while cranking out 17+ghs but after a bit suddenly it dumps the queued work and shuts down, slowly decreasing ghs over time. I am logging the mining output and have captured the log with debugging enabled but I do not know how to decipher what exactly is happening. All I can see is that at some point the program (BFGminer 3.10) suddenly dumps all the queued work as stale and does not reload the queue.
If anyone can help me I would appreciate it as I only have one fan and if I put the 3 on the other PC they get really hot and the error rate goes way up... not to mention I have to run them at a slower speed.
T.
Still trying to earn some coins to purchase a REAL mining rig!

I'm not sure if my experience exactly tallies but I had a similar problem with two powered hubs full of block erupters plugged into a Raspberry Pi B.
Kept shutting down for no readily apparent reason.
Eventually I daisy chained the second hub off the first, so there was only one connection to the Pi and all was sweetness and light.
Might be worth a try?

You hit the nail on the head, I solved a lot of failures and other problems by using a basic low power USB2.x hub as the central place to plug in my Orico USB2.0 hubs that seem to power 7 BEs or ANTs each. Keep in mind you can only reliable daisy chain about 5 levels deep.

So here is the typical scenario:

PC Mobo built in USB hub (1st level) - this one tends to have a lot of internal items like memory card readers and stuff connected
PC Mobo built in USB2 and/or USB3 hub(s) (2nd level) - these are the external ports
User supplied USB hub (3rd&4th level) - central hub all other hubs plug into... those 7+ port low PSU power hubs are good for this
User supplied USB mining hub (5th+ level) - these are the high quality hubs with good high AMPerage PSUs that we plug our miners into.

This is basically my setup and runs very reliably off of a 8 year old laptop.

If you want to read more on this, this guy writes a good deal about this: https://bitcointalk.org/index.php?topic=413406