Question 2PIN vs 3PIN From Specs

Oct 20, 2020
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I am trying to calculate the output of my PCIE PSU cable. I know how to do that based on the number of 12V pins the cable has by checking it visually but there's a chance that one of the pins could be a dummy one and not a 12V one. I know that I can pull out a multimeter and test it but I won't be able to do that for a purchase decision, so I am wondering if there is a way I can find that out by looking at the PSU model specs?
 
Oct 20, 2020
28
1
35
It's for an array of cards + risers. The calculation that I have in mind is multiplying the number of pins with amperes and getting the output. How can I do that just from the spec sheet? Without knowing the number of pins for the PCIE cable.