I decided to dust off the old antminers and set them up again. 

Ive pointed them to szbpool and they work for a few minutes but then bfgminer just stops.  Ive tried both versions of bfgminer and tried using them through med miner assistant and on their own.  Even if I set each antminer to run on its own bfgminer they all stop working at the same time, usually after just a few minutes.  Any ideas?