Thanks guys for the responses, despite the fact that most are in response to the other person.
I've seen the shared chart with maximum wattages a few times and I know I'm not exceeding them. But here's the question:
Is the load evenly distributed across each cable, or is possible that the GPU may overdraw from one cable and not the other?
So if my 3080s are each hooked up with two 6+2s, and one part of that cable powers the riser, is it possible that the card will draw most of what it needs from just one cable, thus potentially overdrawing the cable?
you wont like this answer but the safest way to fix this is as follows.
cable a to jack a in gpu a and an extension to second plug on that cable a plug that into second gpu
cable b. copy that above
cable c copy that above
cable d one to a riser and use an extension to second riser.
this setup insures indentical shared load on all four cable. it also requires four pcie to pcie extensions.
every cable is used on both gpus loads are equal.
do,you need to do this maybe maybe not.
more likely to have runaway tdp on windows then on linux.
i do a few windows and my 125 setting on a single 3060ti does runaway to 195 or 212 once or twice a month.
never happens on my linux based smos.