Currently looking to replace 3 PSU with one EVGA 1600w P2, but have a few questions.
 
Rig is currently pulling 1310w from the wall so would be running just over 80% load
 
Cards are 8x RX580 with 6 using risers
 
I assume there is no reason i cannot use the 6+8 PCIE cables from an EVGA 850w G2 on VGA1 - VGA4? i.e. i can then run all cards using 6+8 PCIE cables
I then need to power 6 risers, i only want to use one riser per cable:
 - 4 can be powered via the 3x SATA and the 1x SATA/PERIF port
 - Can I power a riser from the PERIF port?
 - Can i use the final free VGA port (the 6pin VGA will fit to the riser) 
 
Hard drive will be running from one of the SATA ports (i.e. combined with a riser)
 

Great thanks. Found an old thread which covered off my other questions. 

 

Does the P2 have 5 VGA 8pins to 2x 6+2 pins? or is it 6+2 and 6 pin
 
on my G2, the video cables have 6+2 and a 6pin only.
i got video cards that requires 2 8pins power and to achieve this, i need to use 2 cables to get this done!! (how stupid is this) dumping ~600$ on a PSU to have non proper cables.
my corsair hx1200i has 5 vga -> 2x 6+2 pins! go figure