Ouch, that's a big wattage. So one raiser has a power draws like 1/3 of a 1070.
I'm wondering if the draw is so huge why manufacturers make them with sata connectors? I'm sure they know what is the power limit of the sata connector.
Or maybe older ones with molex adapter draw that kind of power? What raisers do you use?
It's not the risers using the power, it's the GPU drawing 12V through the PCI-E slot. The PCI-E 3.0 specification allows up to 75 W at 12V through the x16 slot. The amount of +12 V and total power they may consume depends on the type of card, some cards pull more from the slot than others. The type of riser makes no difference in how much power the card draws from the riser. I like to use 6-pin risers which have three thicker wires that are designed to spread a higher 12V load compared to 2 for molex and sata connectors. They also use four capacitors instead of three and come with a voltage regulator to prevent spikes.