ASIC block erupter cube help

[Danasd1]

so i got one and hooked it up and everything has been running great for a couple days, but when i try to overclock the cube it makes a click noise and disconnects. anyone know what the problem could be???

[nytrolic]

How are you overclocking it?

What are the temperatures?

[Danasd1]

i go to the configure page and click clock then it changes to the high setting then disconnects

[rulvis]

My guess is the fan,
witch is a part of a safety circuit so the cube wont overheat.
 I think this circuit measure the inner resistanse of the fan comparing it to the 12v rail. when its a mismatch the safety circuit cut the power to the relay and its shut itself off.
When you hit the overclock, the 12 v voltage is dropping (maybe some mV), the circuit is measuring the 12v regarding to the fan current (which is the voltage indirectly and therefor the innerresistance, conf ohm's law, U=R*I). If its a mismatch it turn itself off.
it seems to me that the electrical tolerence of the fan and the safety circuit is very sensitive. Sometimes when i touch the cube i can hear the relay is clicking.
You can test this just to disconnect the fan when the cube is running or partly block the inlet/outlet of the fan so it changes its rpm, and the circuit will switch the cube off. Of you can try with another fan with the same electrical caracteristic. that will maybe solve the problem.
i believe the tolerance for the "fan-part" of this circuit is very small, maybe within a few mA.
A really dirty solution is to bridge the contact point on the relay. But you will then not have a safety circuit in case of overheating!!!

[oxfardk]

it's still dangerous to overclock anyway you need a capacitor to filter out any noise

[iznit]

Check your power supply.  Is it capable of 25 amps on the 12 volt rail?  You need 17 amps to run it normally and 25 amps to run overclocked.