Quote from: Kaimi on January 24, 2018, 01:54:05 PM

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The second possibility I see is the PCIE power port on the motherboard. Should I power both of them with molex ?

As long as you use risers with external power supply - no, no need to power them

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The third possibility I see is a bad BIOS setting

There are no special settings for this setup to work, only handy things like automatically power on system after power outage

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But it's not working, the GPU isn't detected. But if I swap the Molex to 6 pins on the GPU and the 8 pins to 6 pins on the riser, it works
So don't know why it's enough to power the GPU but not the riser ?

Do you have a multimeter? The best way to find out is to check voltage for a start

No, I don't have multimeter. Will try without the molex converter to see. May it will work with 8 pins to 6 pins. (But no enough 8 pins to 6pins slots to power all the 5 GPU + Risers)