[Solarity]

It seems most, if not all blower style 1080 cards and a handful of multi-fan cards have only 8 pin power.

Most after market open air cooled GPUs seem to have 6pin + 8pin. I am thinking that the extra 6pin is there to supply extra power for multi-fan open air GPUs and possibly RGB.

On my MSI 1080 Seahawk EK X and it has an 8 pin as well as a 6 pin connector on it, it also has a RGB header and a fan header, though neither are in use as the GPU came stock with an EK Water block.

MSI also makes another Seahawk non-EK version. This is a hybrid blower + AIO cooler, though this only has an 8 pin. Both of the 1080 Seahawks have identical specs, in terms of GPU and Memory overclock listed.

I have a hypothesis that MSI uses one of two standard cards and that my GPU does not require the extra 6pin power connector. It would be nice if I could verify this some where.

 

[whitrzac]

Only 8pin = Reference PCB(most likely)
8+6ppin = non reference PCB.

It has nothing to do with rgb or fans.

 

[MNMadman]

The PCIe slot can supply 75W to the card.

A 6-pin connector can supply 75W to the card.

An 8-pin connector can supply 150W to the card.

Fans draw something like 3W each, so an extra connector isn't needed for that.

If the PCI power connector is present, the manufacturer expects the card to draw that extra power. There is also the temperature aspect -- more power connectors means each is cooler. Wires can overheat and melt if too much power is drawn through them.

I wouldn't ever not use a PCIe power connector that's on the card. You would be crippling performance if it even allows the system to boot (I have forgotten them before and was warned by the system to power off and plug them in).

 

[WiSK]

If the PCI power connector is present, the manufacturer expects the card to draw that extra power. There is also the temperature aspect -- more power connectors means each is cooler. Wires can overheat and melt if too much power is drawn through them.

Absolutely this. Internally the +12V and the grounds all merged back together into the same power circuit. The different connectors don't have different functions.

So it's about dividing up the power delivered to the board, maintaning a safe current over each wire (just over max 4 amps on the 8-pins / max 2 amps on the wires of a 6-pin).

In reality though the risk of overheating is low, and it would be the plastic connector housing that would melt/combust long before the solder or wires melt.