I'd like to reach out to the OP here.  I'm in a unique position here to possibly help get some clarity on this situation.  I'm an alt coin miner and I just happen to also be a Verizon Wireless technician that works on cell towers as well.  I've had to hunt down my fair share of interference over the years & I'd like to be able to reach out to my co-workers that you spoke with to find out the symptoms of the issue they were working on.

Steamboat.......Just wanted to say thanks for the batch # 6 refund.  I just got the email confirmation, and I see it in my wallet awaiting confirmations.  Too bad things didn't work out, but thanks for hanging in there and doing the "right" thing!

Patiently awaiting my batch #6 refund as well. 

Wanted to bring this back to the first page again.  Looks like a lot of views, but no hits.   

Well after reading over the thread on USB Hubs, and doing my own math, I realized that even though it was a 7 port hub that I was using, the powersuply would only support 6 per hub.  I went through my setup and removed one from each hub, so that I'm only running 6 in each now.  That did the trick!  Now I have 52 of them running perfectly for a combined hash rate of 17Gh/s.

Thanks for the link Trongersoll!  After reading, I reconfigured my set-up using only 6 ports per hub and I'm having much better success!

I don't think overheating is an issue.  They sit right in front of a large fan and right under an AC vent.

I don't know how these guys with 100's of Block Eruptors do it.  I'm trying to run 32 of them off of one Ubuntu 12.10 box running BFGMiner 3.1.4 right now, no matter what I try, I can't seem to get them all to work stable together.  I'm using D-Link DUB-H7 powered USB hubs, and it's kicking my ass.  Anyone got suggestions? Ideas?

Some just don't hash at all when in the big group, but do fine in individual testing.  It's not contained to certain ports either.  The problem just moves around the more I mess with it.   

Just wanted to bring this back to the top of the page.  Anyone south of the Columbus/Macon/Augusta line wanting to schedule a meetup and talk/trade bitcoins?

Sign up over at BTCGuild and once logged in, click on the 'Support' link.  They have a complete guide for Windows & Linux.

I was having issues as well today.  Switched to a different pool and everything seems fine over there.  Not sure what's going on with 50btc right now.

Have you tried physically swapping cards around on the mobo?  How about removing a card that you know works in a particular slot, and moving it to the slot where you are trying add the 5th card.  You'll still have 4 cards, but one will be in the new slot to prove/disprove that the slot is working properly.

A single instance is all you need.  I'm running four 7970 GPU's & ten USB Block Eruptors in the same instance of BFGMiner right now, and it works just fine.

Two things to try:

• Put "http://" in front of the pool URL
• Try pool URL "stratum+tcp://stratum.50btc.com:3333"

A little bit of Google-fu turned up the following link.  Doesn't directly relate to bitcoin mining, you may find something useful in it.

http://www.xtremesystems.org/forums/showthread.php?285341-Load-Mmdriver-has-stopped-working-lt-error

We need more info to help:

• What OS?
• What version of cgminer?
• Make sure to copy/paste any important error or log information as well
• What kind of coin are you mining?

Here is one of many.  Try your Google-fu for others.

http://www.alloscomp.com/bitcoin/calculator

Windows or Linux?

Disregard....I see now that it's Win8.  Unfortunately all of my experience is on Linux, so I'm not sure I have much to contribute now.   

I also had issues running cgminer with the USB Block Eruptors.  After much research and frustration, I found where someone else was having the same issues and switched to BFGMiner.  I tried that on mine, and all of my issues cleared up.  It looks like the cgminer developers are working to understand/resolve the issues with the block eruptors, but for now I'm a BFGMiner convert.

Where are you stuck in the process?  Do you have Ubuntu installed and need to get them mining?  Or do you need to know how to download Ubuntu from the web, and install from scratch?