What do these missing pins do?

philo-sofa

philo-sofa

philo-sofa

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Soo, I'm not sure whether I can safely use this 8-pin to Nvidia 12-pin adapter. Is is safe, anyone know what the missing pins do?

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(n.b. this is a repost, hope that's ok)
 
Tetras said:
You can find the pinout in this post, but in short, there are 6 +12v (the 8 pin has 3) and it is rated for 600 watts (the 8 pin is 150 watts).
https://www.techpowerup.com/269957/...r-its-real-and-coming-with-nvidia-ampere-gpus

A 3060 Ti would likely be fine with a single adapter, a 3070 probably. The 3070 Ti, I would use 2x 8 pin.
Click to expand...
Thanks, that's exactly the kind of thing I was looking for!

Okay so I'm missing pins 1 and 5, so effectively going from three to two +12v cables and from four to three ground cables. So I'm fine for grounds but must be running the six +12v pins with four +12v pins?

So 2/3 the 600w power max means, I guess it should be okay for 400w on a 3090... maybe?
 
philo-sofa said:
Thanks, that's exactly the kind of thing I was looking for!

Okay so I'm missing pins 1 and 5, so effectively going from three to two +12v cables and from four to three ground cables. So I'm fine for grounds but must be running the six +12v pins with four +12v pins?

So 2/3 the 600w power max means, I guess it should be okay for 400w on a 3090... maybe?
Click to expand...

Idk about the pinout, but technically if you're using 2x 8 pins to power a 12 pin then you're limited to 300 watts, with 75 from the slot. At stock that would still be in spec for a 3090 (not including transients), but overclocked it'll exceed it.
 
Tetras said:
Idk about the pinout, but technically if you're using 2x 8 pins to power a 12 pin then you're limited to 300 watts, with 75 from the slot. At stock that would still be in spec for a 3090 (not including transients), but overclocked it'll exceed it.
Click to expand...
As the article says tho, it's not quite a six pin: it's six random pins basically, four ground and two +12v. IDK if the people who made this cable knew what they were doing.
 
philo-sofa said:
As the article says tho, it's not quite a six pin: it's six random pins basically, four ground and two +12v. IDK if the people who made this cable knew what they were doing.
Click to expand...

I have no idea, unfortunately, but if I look at the Silverstone cables (who I assume know what they're doing), they use 6 of the pins in each 8 pin, but the one for their own PSUs, seems to use different pins than the generic adapter they sell.
https://www.silverstonetek.com/product.php?pid=984&area=en
 
Looks like you are missing 2 grounds aka only the 6 pin connections and not the +2, and you are missing pins 8 and 4 (Gnd & Sense B (AKA Gnd))
In short this is a 2 x 6 pin PCIe adaptor
 
Dwarfy said:
Looks like you are missing 2 grounds aka only the 6 pin connections and not the +2, and you are missing pins 8 and 4 (Gnd & Sense B (AKA Gnd))
In short this is a 2 x 6 pin PCIe adaptor
Click to expand...
Looking at the pinout @Tetras linked, it looks more like I'm missing pins 1 and 5 if I've got the orientation right?
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I dunno what to make of this. Perhaps I should drop the manufacturers an email and ask if the cable is correctly put together.

EDIT: the Techpowerup link suggests 9A max per wire, which at 12v would give 108w per wire for a total of 432w from the four total wires. But I'm not an electrician so maybe I'm missing something.
 
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