[jan-jaap]

Voltahe are a bit low. 5v is 4.7 - 4.8 volts i think the psu is cheap, i dont know if this is the the problem.

Toughts ?

The Indigo2 PSU puts out at least 40A @ 5V if I'm not mistaken. ATX PSUs supply only a couple of amperes @ 5V and the rest of their power mostly into 12V rails. If you are pulling that much current into 5V trough a single wire I'm surprised it didn't melt or trigger an over-current shutdown of the ATX PSU.

NB: my 4D/380 rack has a PSU rated for 200A @ 5V. The little two-wire supply wire to the blinkenlights panel at the front of the system shorted at some point. The wire literally exploded: drops of molten copper and insulation everywhere. The PSU was unharmed