Yeah it's very irritating as you can imagine. I made two dummy plugs today, when I started the rig I saw in cgminer that the errant card seemed to go up to full speed for a moment however the whole rig shut down then. I've tried to start it again and one of the cards just shuts the system down with a dummy plug attached. the resistor wire seems a little thin I might try to get some more tomorrow.

Thanks for trying to help Kaz, I'm trying to set up linux on a USB stick to see if this helps..why does your setup need a dummy plug do you know? I think I read on a guide to setting up mining on linux that it wasn't needed sometimes... I have tried googling the issue believe me