Confused about pin cable

pjo123 · 23 Nov 2023 at 21:04

Hi, setting up new pc.

Have this MB

Asus TUF Gaming B650-Plus WIFI (Socket AM5) DDR5 ATX Motherboard

Order Asus TUF Gaming B650-Plus WIFI (Socket AM5) DDR5 ATX Motherboard now online and benefit from fast delivery.

www.overclockers.co.uk

and this power supply

Corsair RMx Series RM750x 80 PLUS Gold Fully Modular ATX Power Supply (CP-9020199-UK)

Order Corsair RMx Series RM750x 80 PLUS Gold Fully Modular ATX Power Supply (CP-9020199-UK) now online and benefit from fast delivery.

www.overclockers.co.uk

one thing is confusing me. The connector at the top of the motherboard has a 4 pin and 8 pin socket.

https://flic.kr/p/2phwHJ1

The cable that goes into the 4 pin is an 8 pin plug that separates into two 4 pin

https://flic.kr/p/2phqzKA

I presume looking at the picture I use the right hand 4 pin, the 4pin with CPU printed on it?

many thanks

pjo123 · 24 Nov 2023 at 10:51

Had a good Google. It appears I can use eithe, I used the one with CPU printed on it and it worked fine.

ronemca · 14 Jan 2025 at 02:33

I'm having a similar issue, and I can't get ANY life out of the system at all so far. Note that I have no HDD's...no SSD's...and no M2 drives installed yet. But I would expect the fan to come on at least. But it's dead. HOWEVER...

This business of the 8-pin socket and the adjacent 4-pin socket may be the culprit. I have the 8-pin connector (2x4-pin snapped together just like your pic) from the modular PSU. And--without separating it--it matches the 8-pin socket on the mobo. But I have nothing for the 4-pin socket.

I agree that by separating the 8-pin into two 4-pin plugs I can insert either of them into the 4-pin socket. But that leaves me with nothing to fill the 8-pin socket!!

What is the magic combination that works, please? AND - BTW - am I right to expect the fans to turn on even though there are no drives installed? It should still do something, shouldn't it?!

SpellowHouse · 14 Jan 2025 at 05:36

Unless you are overclocking then you don't need the second one. When they first appeared it was common to leave then without anything plugged in.
BUT some motherboards demanded you plugged something in. They wouldn't work unless you did. In that case you need to buy another CPU power cable from the manufacturer. They usually cost about £5.

ronemca · 14 Jan 2025 at 12:19

Thank you. Interestingly, I yanked the 24-pin connector off the mobo & attached my PSU tester. Whaddya know - when I flip the switch on the back of the PSU I get absolutely nothing. No sign of life whatsoever . So I'm off to the retailer to swap the [apparently dead] PSU. Stay tuned - will follow up.

ronemca · 15 Jan 2025 at 14:30

Sure enough - the PSU was absolutely DoA. This was a BNSIOP 'BeQuiet' 550W unit. I have never heard of 'BeQuiet' devices, but the tech fellow at my local store opined that they were a good brand. Hmmm. In an case, I swapped it for a BNSIOP Corsair 550W unit, and all is well. (And not surprisingly, the new PSU also did not come with a 4-pin connector. And as Soldato said - it was not required. I stuck in the 8-pin (and of course the 24) and away we went. Now I'm just waiting for the Gen5 NvME 1TB drive, and I'll be off & running!
Many thanks!