8 Pin CPU Cable = 2x4 pin?

[Tomha]

I notice many power supplies including some of Corsairs more premium ax series such as the ax850 still dont come with an 8 pin cable which some motherboards have. I have heard it is suitable to use 2x4 pin cables, but I want to be sure. Can anyone confirm/deny this for me?

Thanks

 

[Night Hawk]

For AMD boards most models only use one of the two 4 pin plugs as a rule. For Intel models that use 8 pins you would simply plug both 4 pin plugs in together to represent one 8 pin connector. You simply line the two up side by side when going to plug them in.

 

[Tomha]

Right, so a AX650W PSU from Corsair, comes with 8 "4 Pin Peripheral Connectors", I would just use 2 side by side on a Intel z77 board?

 

[Night Hawk]

I just dropped a 600w model on one old case here I'm trying to get running that see two 4 pin plugs for cpu and two for video card. This is why you would typically see four 4 pin plugs with a slight difference when looking over the two separate pairs in the size of the plugs.

The pair for the cpu will be a separate rail by itself where the sleeve is as heavy as the ones for the sata and ide connectors to distinguish those apart from the two available for SLI or Crossfire setups if not running a single video card. Once you stretch the cord out and bring the correct pair over to the cpu power connection on the board you can match up the right ones by size and locking tab on each plug.

 

[bobkn]

Right, so a AX650W PSU from Corsair, comes with 8 "4 Pin Peripheral Connectors", I would just use 2 side by side on a Intel z77 board?

Nah.

The "4 pin peripheral connectors" are the old Molex connectors commonly used on PATA (IDE) hard drives and optical drives.

You'd use the 8 pin EPS connector, which can be split into two 4 pin ones.

 

[Night Hawk]

Have a look at the two types of plugs being described here. When scrolling down the right side of the Wikipedia page here you will see 3 photos first being the back of a power supply. second 24pin main connector and single 4pin cpu power feed, and the last the standard molex type connector for ide hard drives and ide optical drives as well as an alternate power feed for the old Sata I type hard disks. Molex connector - Wikipedia, the free encyclopedia

Now simply type cpu power connector 8 pin or other on the Bing search engine to see a page full of various cpu power feed connectors. cpu power connector 8 pin - Bing Images

This will help distinguish the differences between the different types of 4 pin plugs.

 

[Tomha]

Gotcha. The power supply should arrive tomorrow, then I can check I got it all sorted. Until then though, thanks for the help

 

[Night Hawk]

With the 600w Corsair I will be putting to use once a replacement board arrives on the old case that sees a separate rail for the cpu power. You likely will find the one you get in will be the same since that's how that brand manages the connections.

The rest is simply getting familiar with where everything is located on the board itself. That's where going over the general layout as well as all of the sections in the board's user manual is an even larger help.

 

[Tomha]

I got the general layout of motherboards sorted, this is just the first time ive encountered the 8 pin plug for the cpu, and my hx650 I use currently doesn't have any kind of 8 pin connector, I just wanted to be sure.

 

[Night Hawk]

Most of the time you will see the 4 pin used. But this also depends on a few things like the cpu socket type and it's requirements since they vary as well as the model line the cpu comes from.

Generally the 8 pin will be found on an Intel not AMD board. Often that depends on the board manufacturer at this point and what the board has on it. A dual cpu server board would certainly use it!

 

[Phone Man]

I got the general layout of motherboards sorted, this is just the first time ive encountered the 8 pin plug for the cpu, and my hx650 I use currently doesn't have any kind of 8 pin connector, I just wanted to be sure.

That HX650 should have the split 8 pin hard wired on the power supply. The main cable is a 20+4 and the 2nd is the 4+4. Is your unit different?





Jim

 

[Tomha]

No, that was my bad I just went and checked and I do indeed have the 8 pin wired in, it looked like a 6 pin from the angle I was looking at it from.

 

[smarteyeball]

Right, so a AX650W PSU from Corsair, comes with 8 "4 Pin Peripheral Connectors", I would just use 2 side by side on a Intel z77 board?

You will find that two of the 4 pin connectors when 'pushed together' have notches that will make it look like, and act, like on 8 pin CPU connector.

(I'm pretty sure the HX has the same)


Intel boards can run off one 4 pin CPU connector, but for better and a more even load/current distribution/draw it's always best to use the 8 pin. Especially when overclocking so it doesn't draw too much current from the one connection. overvolting on one connection can lead to burning the connection.

 

[Night Hawk]

That would be pulling too much amperage through a connection can heat it up enough to see it melt down on you! By that time however the overheat protection circuit would likely be kicking in.

When you look at the detachable 4 pin connector seen on the main 24 pin and how that fits together that's how it would be for the twin 4 pin cpu feeds is what smarteyeball is pointing out there. On and AMD board however someone could possibly ask which of the two to plug into the single 4pin cpu feed? One or the other!

Don't fret none! The 750TX model also sees the pair of feeds on the separate rail as well but offers an extra rail for drives being a heavier supply.