Just out of curiosity, what USB hubs are you guys using? My Ankers for some strange reason do not work anymore, on either windows or linux. Must be some sort of weird usb 3.0 bug in those hubs, or some weird cgminer issue.
Finally got use out of my Mondohub 28 port !
Where possible, try using USB 2 ports vs USB 3 ports, I've found.
Yep, my Ankers are totally worthless. I just got a Belkin 2.0 7-port powered hub (2.0 amps max) from Best Buy, and it did the trick.
On another note, one of my Klondikes must have had it's fan connector disconnected by me brushing up against it while I was connecting another one, and it sat there, heated up, and SPOOGED a huge wad of creamy thermal compound all over the table and my hand...
I've been real happy with my Rosewill RHB-500s (10 ports). I have over 20 of them. It's too bad they don't seem to be available anymore.