Powered or unpowered risers?

Hello Fellow miners
My motherboard board has 4x 16x pcie slots with a additional 6 pin cable for powering the pcie slots (
Gigabyte Z87X-OC Motherboard ), I currently have 2 x rx 470 nitros and plan on getting 2 more inside a corsair 540 air case, i plan on modding the case to hold 4 cards so each card has enough room to breath.
would i need powered 1x risers, or could i get 16x risers unpowered risers and connect the gpus that way.
When i'm done mining i would like to use this rig for rendering in blender also.

My psu is a fractal design newton r3 platinum 1000w

Thanks in advance!

Always use powered risers, especially on any GPUs with only 1 PCIe connector

More things have gone wrong using powered risers for me. I'd go with unpowered ESPECIALLY go if your motherboard has a molex connector which you are powering from the PSU. Too much power on the PCI-e bus is worse than not enough.

The Asrock H81 pro BTC have the molex connector, so it's better to use unpowered riser, isn't it?

Yes. I think so. As I said, too much power on the PCI-e buss can be worse than not enough.

Always, but always, powered.