Power Adapter/Cable Question

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Cod

Gawd
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Mar 21, 2003
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If I buy a GPU that uses a 1x8-pin power connector, can I use a 6-pin to Dual 8(6+2)-pin cable to connect the GPU to my PSU? My PSU (Seasonic M12II old model) only has a 6-pin connector leaving it, while the GPU (MSI 1060) I'm thinking about requires an 8-pin connection.

Any help is appreciated. Thanks.
 
6 pin to dual 8 pin? E.g. one 6 pin two two 8 pin leads - No.

But 6 pin to 8 pin is fine. It binds a positive on the 6 and borrows a negative.

Your PSU should have specs on the maximum amperage draw for that cable. Don't exceed it.

Trouble is that one positive wire is going to carry double the amperage it would have. But it should be okay. Call Seasonic to double check. You'll need the amperage draw specs for that 1060.

You might want to just upgrade PSU's. 600 watts is plenty, but not coming with an 8 pin is an indication that it was not built with that in mind.
 
Last edited by a moderator:
Cod said:
If I buy a GPU that uses a 1x8-pin power connector, can I use a 6-pin to Dual 8(6+2)-pin cable to connect the GPU to my PSU? My PSU (Seasonic M12II old model) only has a 6-pin connector leaving it, while the GPU (MSI 1060) I'm thinking about requires an 8-pin connection.

Any help is appreciated. Thanks.
Click to expand...
According to the [H] review your PSU should come with an 8-pin PCI-E cable.

Overview - Seasonic M12II-620 Power Supply Review
Kwaz said:
6 pin to dual 8 pin? E.g. one 6 pin two two 8 pin leads - No.

But 6 pin to 8 pin is fine. It binds a positive on the 6 and borrows a negative.

Your PSU should have specs on the maximum amperage draw for that cable. Don't exceed it.

Trouble is that one positive wire is going to carry double the amperage it would have. But it should be okay. Call Seasonic to double check. You'll need the amperage draw specs for that 1060.

You might want to just upgrade PSU's. 600 watts is plenty, but not coming with an 8 pin is an indication that it was not built with that in mind.
Click to expand...
According to the MSi FAQ the 1060 requires 20A on the +12V rail. Each rail on the OP's unit supports 24A according to the [H] review above. The review did note a dip in the +12V of 0.4V at full load, but even a system with an overclocked i7-6700K and a GTX 1080 probably isn't going to break 400W during regular gaming.

Power requirements for graphics cards
 
Armenius said:
According to the [H] review your PSU should come with an 8-pin PCI-E cable.

Overview - Seasonic M12II-620 Power Supply Review

According to the MSi FAQ the 1060 requires 20A on the +12V rail. Each rail on the OP's unit supports 24A according to the [H] review above. The review did note a dip in the +12V of 0.4V at full load, but even a system with an overclocked i7-6700K and a GTX 1080 probably isn't going to break 400W during regular gaming.

Power requirements for graphics cards
Click to expand...

I think that the PSU itself will be just fine. It's the wires I'm not sure about. But they should be adequate gauge, especially from Seasonic. Is there an ATX spec for wire gauge?
 
Kwaz said:
I think that the PSU itself will be just fine. It's the wires I'm not sure about. But they should be adequate gauge, especially from Seasonic. Is there an ATX spec for wire gauge?
Click to expand...
18 AWG is the standard, if I'm not mistaken, but it can vary between manufacturers. Corsair generally likes to use a thicker gauge on their PCI-E cables.

In short, I don't think there is a specification that defines what gauge wire is to be used.
 
Thanks for the replies. I'll have to look again at my PSU, but I didn't see any 8-pin connectors. Also, I swear it wasn't fully modular when I bought it...there were 3 main cables that were "part of the unit" and 2 extra 6-pin slots that were modular.
 
PCie 6pin power connectors are supposed to only have two +12v feeds, but most power supplies have three. Since the 8pin connector only has three +12v feeds, there's no issue using a 6->8 adapter on one of those.
 
So there is an 8-pin already part of the PSU, but its powering the motherboard. There is also a 4+4-pin coming from the PSU, which is not hooked in. Can I use this 4+4 for the GPU or the motherboard? Am I back to my original thought, using a 6-pin to 8-pin adapter?

Thanks again for all the help.
 
4+4 should be connected to the motherboard it's split because some m/b may only have a 4 pin connector. The 8 pin should be marked PCie either on the cable itself or on the output of the power supplies body make sure it's marked as such do not use a m/b connector on the card. There should be some documentation with the power supply specifying which cable is for which.
Edit checked the mentioned review of that power supply the 8 pin is for PCie and the 4+4 is for the m/b.
 
To be more precise, the 4+4 pin cable is EPS that provides extra power to the CPU. The pinout is different and you should not attempt to use with PCI-E graphics cards. If I'm not mistaken, the shroud casing is different anyway, so you wouldn't be able to plug it into a PCI-E power receptacle without using a stupid amount of force.
 
I guess I find it funny that people who think they always know what they are doing will fry something first before taking a little time to RTFM. Always assuming that their own knowledge is always good enough.

So many things can and do change and a little manual reading can save a lot of grief, embarrassment and money.

This isn't in reference to the OP, just a random thought that just popped in my head.

Carry on.
 
MrGreg62 said:
4+4 should be connected to the motherboard it's split because some m/b may only have a 4 pin connector. The 8 pin should be marked PCie either on the cable itself or on the output of the power supplies body make sure it's marked as such do not use a m/b connector on the card. There should be some documentation with the power supply specifying which cable is for which.
Edit checked the mentioned review of that power supply the 8 pin is for PCie and the 4+4 is for the m/b.
Click to expand...
Thanks for sharing that. I guess I never really looked into using the 4+4 for the m/b. The manual for my m/b just mentions using an 8-pin connector (not specific about 4+4, 6+2, or straight 8). I'll re-open my case tonight and plug the 4+4 into the m/b...then the straight 8-pin will be freed up for a new GPU. Thanks again.
 
I didn't think a PCIe 8 pins would fit in a mobo 8 pins TBH...

--- edit --
Apparently they can

iur
 
So I used the 4+4 connector for the motherboard; however, I don't think the 8-pin coming from the PSU is meant for a GPU. The connections look different from the images I've seen of GPU connection points. Am I just seeing things? Or are there different types of 8-pin connections from a PSU?

For example, this 8-pin connection on the HIS RX480 doesn't match the picture posted: http://cdn.videocardz.com/1/2016/08/HIS-RX-480-ICEQX2-Roaring-Turbo-side-logo.jpg.
 
Cod said:
So I used the 4+4 connector for the motherboard; however, I don't think the 8-pin coming from the PSU is meant for a GPU. The connections look different from the images I've seen of GPU connection points. Am I just seeing things? Or are there different types of 8-pin connections from a PSU?

For example, this 8-pin connection on the HIS RX480 doesn't match the picture posted: http://cdn.videocardz.com/1/2016/08/HIS-RX-480-ICEQX2-Roaring-Turbo-side-logo.jpg.
Click to expand...


Looks like the picture is slightly wrong. Pin 8 is supposed to be square. Now on the PSU side, they can use any keying they want as long as +12v goes where it's supposed to and gnd does too. So it's possible that EPS12v and PCIe 8pin could be powered from the same PSU side socket.
 
ryan_975 said:
Looks like the picture is slightly wrong. Pin 8 is supposed to be square. Now on the PSU side, they can use any keying they want as long as +12v goes where it's supposed to and gnd does too. So it's possible that EPS12v and PCIe 8pin could be powered from the same PSU side socket.
Click to expand...
So pins 1, 7, and 8 should be square? Is this true of all PCIe 8-pin connectors?
 
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