GPU's keeps blowing up PSU's

I have a little problem with my power supply's.

Here is the details.

1 x ASRock H97 Anniversary
6 x R9 290's
2 x Thermaltake - Toughpower GOLD 1000W
CPU, Memory, HD Drive.


My problem is i keep blowing up the GPU port in the power supply's.

I overclock a little

Core Voltage (mV) +0
Power Limit (%) +0
Core Clock (MHz) 1080
Memory Clock (MHz) 1250
Fan Speed (%) 85

I have killed two PSU now, I was thinking 2 x 1000W would be ok.
I don't know nothing about the Core Voltage and Power Limit stuff
so i didn't want to play around with then.

Surly 2 x1000W PSU's are fine for 6 x GPU's ?
3 GPU's on each power supply.

Am i missing something ?