Seems to be a big no no to power risers off sata. My rig will consist 4x 1080 Ti's. only two are hooked up now directly to the mobo.

My risers are the version 7's that have a 6 pin PCIe on the pcb and come with 6 pin to sata adapters. Now I only plan on running the cards up to 60% power target max which is 150w. The 1080 ti's have 8+6 pin which is good for 225w. From what I gathered it seems so long as I stay below 225w the card won't draw power from the riser. Is this right?

I am using an EVGA 1300w PSU and was going to power 2 risers per PSU sata cable.