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I see however, the problem rather be the CGminer itself, because it deregulates the stick for wathever reasons
...
'wathever reasons' is the problem.
Often as simple as a power source issue.
Hello Kano,
Thank you for your reply.

I've got a gekko usb hub with 120W PS and a fan running beside this miner. The power consumption of these can't be more than 5V/3A=15W + 5V/2,5A=12W, Sum: 27W, which is covered with the 120W PS abundandtly.
If I run two other miners + the fan there are no problems. They are running rock solid so the PS can't be a problem.
If I put this problematic miner in usb-port-pair with the others, it kicks the others out and they restarts automatically in about every 2-3 minutes.
If I run it beside them - not in a port-pair -, the two are running stable and this one is restarting with a reduced T until it gets to a point where the T is in the (-) minus range... Than it kicks the others out as well and they stop working.
I'm starting cgminer with the following line:
--gekko-compacf-freq 420 --gekko-start-freq 350 --gekko-mine2 --gekko-tune2 85
Now I lost nerves playing around with them days long without any success and let the 2 unproblematic without the other one running.
