Hypothetically, if you have a graphics card that draws say 200-250 Watts and is powered by 2 8pin connectors, would it be better to use one wire diasychained with 2 connections or 2 seperate wires coming from the power supply? The power supply is all on the same power rail and over the capacity of wattage for the entire system.

Short answer: your choice as either will work just fine.

Thanks brah PC world is full of *******s that over do every little thing. I dont think most pc dorks understand how electricity works and say oh its BETTER for the card if you use 2 wires instead of one. Its my understanding that it makes ZERO difference as long as you arent over amps.

you'd have slightly less resistance in the configuration with two parallel wires, but it would have no material impact on anything

I run my 3080 off 1 piggy back and another 8 pin and it runs great it still hits boost clocks of 2050 easily so a piggy back connector will work just fine in your case

quality of power delivery is important too, that's why nvidia had problems on the 3090 launch because some OEMs were power filtering through different types and groupings of capacitors

real world, it only matters at high end overclocks for stability's sake, 1 pigtail cable will get the job done for a lower wattage card although you have to deal with the aesthetic problem of having that weird pigtail twisting around at your GPU

not sure what any of those photos have to do with the question though, that 1st one is the new nvidia 12pin and the 3rd is a dual 6pin which i think is AMD's usual standard?

I was just trying to give a visual example for Electrician brahs the first image doesnt mean anything.

This. Should be no issue either way.

I've had this thread open in a tab all day on my personal PC, might as well finish up a response to it.

Short answer is: use two cables, brah.

Long answer...

Each one of those 8-pin connectors is rated to output 150W, which is 12V @ 12.5A. The wire has resistance, and you are going to get some voltage drop sending 12A current across that resistance (V = IR, right brahs?). So when you're pulling max load from the power supply, the actual output at the graphics card might be maybe 11.5V @ 12.5A. But that's gucci. The card is designed to function with 12V plus or minus some tolerance range.

When you pull 250W through one connector wire, that's 12V @ 21A. V = IR, so doubling I across the same R droops the voltage by double compared to its max rating. I'm banking your graphics card isn't rated for 2x beyond spec droop. So at the most hardcore/intense part of your gaming when you're drawing max power for the GPU, it might throttle and slow down to self-regulate its voltage back to a normal range, or just like trip a fukking internal breaker and hard-shutdown your rig right in the middle of your game.

And that's if your wires doesn't melt. V = IR? Well heat = power = I^2 * R. Double the I and the heat goes up 4x. Your cables are spec'ed to withstand a normal current draw without breaking or melting, expose them to 4x that limit for a couple hour gaming sesh and they won't be happy about it.

And then there's other little gremlins that could creep into your system. That big extra droop from the over-drawn voltage will pass on more noise to your data lanes (the part you plug in to the mobo) than it's spec'ed for, corrupting some bits and making 0s sent by the GPU read like 1s to the computer. This could cause weird bluescreens and driver glitches that you won't know the cause of, because pretty much no online guide out there is going to cover something as esoteric as PDN noise.

Sauce: I debug power connections to chips as part of my day job. Before working here, I would've said "just cowboy it brah, daisy chaining isn't going to hurt chit", but after analyzing the problems that come with breaking power draw specs like every other fukking day, I'm not as sanguine about it.

It's 1 fukking extra cable, brah. Do it for the hardware engineers.

This guyhttps://www.moddiy.com/pages/Power-S...d-Pinouts.htmlis saying the true capacity for those connectors is like 336 watts removing the safety factor. So I dont think they will melt. But yeah when its over the spec, I would just use two cables and have piece of mind.