I'm inteding to run 6 R9 280X cards on an Asrock H81 Pro BTC board.
The cards have x16 PCI-E, 6-pin, and an 8-pin connection
The board has 1 PCI-E 2.0 x16, and 5 PCI-E 2.0 x1 slots.
The board also has 2 4-pin molex connections for extra power.
I will use 5 PCI-E x1 to x16 adapters for the x1 slots.
The adapters have a 4-pin Molex connected to them.
I will use 2 identical 1250W power supplies.
The cards will run at full load at all times
The only other components in the system are negligible.
My question is what would be the best way to connect the power supplies so that the load is equally shared?
Is the following scheme sensible?
Power supply A:
24-pin motherboard power
6-pin and 8-pin connectors of cards 1,2,3
4-pin molex connector on x1to x16 adapter of cards 4,5,6
Power supply B:
2x 4-pin molex connectors on motherboard
6-pin and 8-pin connectors of cards 4,5,6
4-pin molex connector on x1to x16 adapter of cards 1,2,3
Is there a better way to connect? How is the power consumption distributed between the PCIe, PCIe 6-pin and PCIe 8-pin? (I know the max possible wattage is 150w 75w and 150w respectively)
I don't know how the motherboard distributes the load to the PCIe x1 slots between the 24-pin power and the extra 2 4-pin molex, but maybe some here knows.