Be Quiet! Straightpower 11 1200W - Weird Cables?

edamr · 6 Jan 2023 at 12:44

Hi all

I've just upgraded my PSU but a little troubled by the cables. It's a bit odd as I'm normally not stumped by this. Maybe its new standards or something, it has been a while since I've done a build.

My motherboard (Gigabyte X570 Gaming X) has an 8-pin CPU power header.
The PSU has a connector for 'MB' which has an 8 pin plug, plus the usual ATX power connector.
The supplied 8 pin CPU power cables with the PSU both have a 10 pin connector one one end, and 8 on the other (1x 8, 1 x 4 + 4).

This means whilst I can connect to the MB with either of the 8 pin headers, the other ends are 2 pins too big for the 'MB' socket on the PSU!

The manual suggests that the 8pin CPU cables can plug into the 'P8' connector on the PSU, which has a 10 pin hole. There are two 10 pin 'P8' connections on the PSU.

This seems to work.

Question - have I done this wrong and if not

a) what the point of the 8 pin 'MB' connection on the PSU; and
b) why ship with CPU cables that have 8 on one end and 10 on the other?

Cheers

Tetras · 7 Jan 2023 at 07:01

I'm not sure if I entirely understand what you're saying, but if I'm correct: you're asking, why are the connectors different on each end? The reason is, the motherboard 8-pin is a standard (EPS12v), modular PSUs are not, so they use whatever the PSU manufacturer decides they need to use. Often, you can plug cables into the PSU, that support more than one device, e.g. CPU or PCI-E, molex or SATA, but if you did that at the device end, then bad things would happen.

edamr · 7 Jan 2023 at 08:02

Yeah sorry if that wasn't clear. Putting it simply:

Why have Be Quiet supplied an 8pin CPU connector with a 10 pin connection on the PSU end, when there is only an 8 pin socket for the CPU supply on the PSU? Basically - it doesn't fit in the PSU!

DeathStorm · 13 Jan 2023 at 01:41

edamr said:
Yeah sorry if that wasn't clear. Putting it simply:

Why have Be Quiet supplied an 8pin CPU connector with a 10 pin connection on the PSU end, when there is only an 8 pin socket for the CPU supply on the PSU? Basically - it doesn't fit in the PSU!

Isn't that smaller MB port for the main ATX cable (20+4) and the 8 pin cable (EPS12V) uses one of the PCIE ports (it's just the cable that's wired differently)?