Quote from: thoughtcourier on December 17, 2013, 04:16:00 PM

Quote from: allinvain on December 17, 2013, 02:33:10 PM

Quote from: crumbs on December 17, 2013, 02:01:21 PM

Quote from: arorts on December 17, 2013, 08:24:38 AM

Quote from: allinvain on December 17, 2013, 08:12:42 AM

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I also observed a funny phenomenon where the system slowly overclocks itself. Essentially the resistance on the h-cards at the R02 resistor lowers itself with time. Don't ask me how this happens, but it may be somehow the way I pencil modded them? I dunno, either way I'm hoping that it will remain stable for now.

Anyways, wrong thread for this discussion.

Yes, that's true!! The R02 resistor lowers itself with time. I guess the hot carbon sitting in that resistor becomes more "resisting" over time?? I've consistently seen this effect as well. I used HB pencil. A good experiment is to use H2 or harder pencil to see if it has the same or worse effect.

This is pretty odd, when carbon resistors age, the resistance *always* goes up (as in 1k resistor will become 1.1k). Weird.

Yeah it makes no sense to me either. I would expect as some of the carbon falls off essentially what should happen is seeing as how there are fewer carbon chains there the resistance should go UP and thus the cards should begin to slow down in hashing performance as the voltage drops. I guess there must be some other factor that I am not aware of. Maybe the extra heat is causing some of the solder around the resistor to change shape and perhaps causing more contact or some voodoo like that?

Anyways, I just hope that these babyjets don't start melting my PSU cables like the bitfury units.

Not to embarrass anyone, but I will have to say that you can't measure the passive resistance of a device that is on with a multimeter. It makes a lot of sense that the multimeter is measuring a slowly decreasing resistance when that happens. (Exceptions apply, but this is probably not the case here)

The device is not on when measuring the resistance. Because these blades sit in a backplane parallel to each other at close quarters, it is damn near impossible to measure electricals while it's running, unless of course you have just one board or a few boards active and there is ample space between the boards.

I measured the ohm on the R02F resistor while the board was out of the rig and completely powered off.