Now New problem I purchased 2 coolmax PSU and they are rated for 750w @57a and for some reason they are not powering up when connected to the power distribution board. Does both PSU have to match for it to work? are the 2 6 pins are inter changeable? Not sure what's going wrong but it does not power up. I can do the paperclip trick and it runs but it will not power the blade. I'm halfway there just need to get power to the other blade. Anyone know this answer?
If you have any of the PCIe/CPU plugs swapped, then your unit will not start. Luckily, that particular problem is well-protected, and there is no damage. So, check that you have the right plugs in the right places. At first, I did that twice while swapping power supplies, but now it's 2nd nature. See my earlier post with pics of what should go where at:
https://bitcointalk.org/index.php?topic=379819.msg4557614#msg4557614