Quote from: droghtak on September 12, 2017, 12:19:12 PM

So only thing is to have all gpus powered by the same PSU but I can power GPU0-2 with one PSU and GPU4-6 with other PSU right?

Exactly, power the riser and the GPU in that riser from the same PSU and it should be fine. Like this: PSU1: ATX, CPU, GPU0 in x16 slot, GPU1, Riser 1 PSU2: GPU2, Riser 2, GPU3, Riser3 etc.

Quote from: droghtak on September 12, 2017, 12:19:12 PM

I wonder why there are a lot of threads about grounding PSUs together ...

Honestly, I havent seen a single thread discussing that but im new here Grin

I can think of two reasons where you would talk about such a thing:

1. The basic principle is having a common ground for all electrical loads together. If you look at your entire rig as one circuit then you might consider connecting grounds. But if you connect a GPU and its riser to PSU2 then you have an independent circuit as none of the consumers is connected to PSU1 and therefor dont need to connect grounds.

2. To power on the 2. PSU you have to ground a pin on the ATX plug (thats what usually the power on switch does when you press it...but thats connected to PSU1 so you have to forward that signal somehow to PSU2). People use an "add2psu" thing for that.