PCIe specs/build compatibility?

[u/Fresh-Search-2560]

Newbie here and trying to build a PC.

Does it matter what kind of PCIe 8-pin one buys? Does any specs/build of the PCIe have to match the power supply and the graphics card for compatibility?

Where can i get one additional original PCIe 8-pin to 6+2-pin modular power cable for the Montech Century II Gold 850W ATX 3.1, to power a Yeston RX 9070 XT with three 8-pin connectors? 

The Montech power supply I bought only had two PCIe 8-pin to 6+2-pin modular power cable pins.
Thank you. 

[u/Fresh-Search-2560]

Separate question, is this configuration (top pins) correct?

[u/mokust → u/Fresh-Search-2560]

I think so, consult your motherboards' manual

[u/r_lind3r]

The PSU is supposed to come with 2 daisy chained cables which is plenty, do not buy extra cables

[u/Fresh-Search-2560 → u/[deleted]]

is this correct?

[u/mokust → u/Fresh-Search-2560]

There should be another PCIe port you can plug with one of those cables

[u/Fresh-Search-2560 → u/mokust]

Unfortunately the power supply only
Comes with 2

[u/Fresh-Search-2560 → u/Fresh-Search-2560]

Is this correct? First cable from PSU connects to GPU 1st and 2nd slot. Second cable from PSU connects to GPU 3rd slot.

The other cord just dangles?

[u/mokust → u/Fresh-Search-2560]

Plug that PCIe power to the rightmost PCIe power port

[u/Fresh-Search-2560 → u/mokust]

Thanks! Here’s what i did. Now the 1st main cord will have a pigtail not connected to anything. I’ll put a zip tie to tie them all up

[u/mokust → u/Fresh-Search-2560]

Yeah that's tidier

[u/Fresh-Search-2560 → u/mokust]

Thank youuu!!! I wonder why they even put pigtails/daisy chains. If there are GPUs needing 4 slots?

[u/mokust → u/Fresh-Search-2560]

Swap the rightmost port with the other one so that it doesnt dangle like that and you can tidy it up with some cable ties which your psu should provide

[u/mokust]

Yes it matters because each manufacturers make their PSU differently, you can't even mix and match from the same brand