4 pin ATX power connector

[Hotrod2go]

I have a curious issue with my motherboard > MSI B450 Gaming Pro Carbon AC
It's to do with the additional 4 pin ATX connector for the CPU. I already have the 8 pin connector for this header connected up but there is space for another 4 pin header next to it.


The problem is my PSU (signature) does not have this available for extra CPU power connections even though it was purchased last year when I acquired this mobo. So it's not exactly out of date.

This is what I have to work with as demonstrated in the pics.

So my question is do I have to configure an adapter (if 1 exists!) to plug into one of the other unused connections on the back of the PSU panel or what? because I have never seen this type of connector before next to the already established 8 pin connector for CPU that has been around for yrs already on mid to high end mobos.

 

[ShrimpBrime]

Molex to 4 pin atx adapter my friend. You can get these for fans and pci-e sata ect.




https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/322262238120

 

[Hotrod2go]

Molex to 4 pin atx adapter my friend. You can get these for fans and pci-e sata ect.




https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/322262238120

Hmmm, ok, I was skeptical of those things, got a couple of them laying around somewhere here but the ones I've seen on ebay say they for Pentium 4... in any case, weird how MSI have done that with a 2018 mobo.
If I set that up & start pushing for higher CPU clocks, won't it start drawing too much power from that type of connector.?

 

[WhitehawkEQ]

With the Corsair PSU's I have I get 2x8 pin cables, 1 of those 8 pin cables has 2x4 pin connectors, they can be used in a 8 pin MB connector or use just 1 4 pin connector for 4 pin MB connector.
I don't know what power cables your PSU comes with but check in the box and see if you have an 8 pin cable with 2x4 pin connectors on 1 end. You might even buy 1 from NewEgg or other PC stores. Oh and when in doubt, use all the connectors on the MB.

 

[DaveB]

Hmmm, ok, I was skeptical of those things, got a couple of them laying around somewhere here but the ones I've seen on ebay say they for Pentium 4... in any case, weird how MSI have done that with a 2018 mobo.
If I set that up & start pushing for higher CPU clocks, won't it start drawing too much power from that type of connector.?

You're overthinking this. These connectors work fine, I've used them for years. Just plug in one of the adapters you already have and be done with it.

 

[ShrimpBrime]

Hmmm, ok, I was skeptical of those things, got a couple of them laying around somewhere here but the ones I've seen on ebay say they for Pentium 4... in any case, weird how MSI have done that with a 2018 mobo.
If I set that up & start pushing for higher CPU clocks, won't it start drawing too much power from that type of connector.?

You dont even need to use the connector. It probably wont even do anything for you at all.
Unless maybe you have an LN2 pot on the board we arent aware of.

 

[Super Nade]

The correct and safe approach is to look at the wire configuration in your motherboard. In you manual see page 35:
http://download.msi.com/archive/mnu_exe/mb/E7B85v1.2.pdf

The 4-pin connector pin-outs are:
1-GND
2-GND
3- +12V
4- +12V

Now look at your PSU connectors:
https://silverstonetek.com/downloads/Manual/power/Multi-PSU-Manual.pdf
Your manual (assuming I got it right) shows a 4-pin connector (page 4). If you find it, use it. If not, use the legacy Molex:
Molex:
Yellow- +12V
Red- +5V
Black- GND
Black- GND

You want to buy an adapter that maps both grounds and only the 12V. Since the 4-pin connector has two wires, assume that you will be drawing enough current which necessitates 2 wires, so use an adapter that requires two molexes. This is an extreme case. In your use case you can get away with having a single molex to 4-pin adapter. It is hard to screw this up as these are ATX standardized.

Good luck!

 

[Zerileous]

With a 3600X am I the only one thinking a single 8 pin is more than enough?

 

[Super Nade]

Yes, it should suffice but now he has his options.

 

[Hotrod2go]

Yes, it should suffice but now he has his options.

Ordered one on ebay after looking at what I thought were the ones that would work but they are for molex to 6pin gpu connectors from eons ago...

The correct and safe approach is to look at the wire configuration in your motherboard. In you manual see page 35:
http://download.msi.com/archive/mnu_exe/mb/E7B85v1.2.pdf

The 4-pin connector pin-outs are:
1-GND
2-GND
3- +12V
4- +12V

Now look at your PSU connectors:
https://silverstonetek.com/downloads/Manual/power/Multi-PSU-Manual.pdf
Your manual (assuming I got it right) shows a 4-pin connector (page 4). If you find it, use it. If not, use the legacy Molex:
Molex:
Yellow- +12V
Red- +5V
Black- GND
Black- GND

You want to buy an adapter that maps both grounds and only the 12V. Since the 4-pin connector has two wires, assume that you will be drawing enough current which necessitates 2 wires, so use an adapter that requires two molexes. This is an extreme case. In your use case you can get away with having a single molex to 4-pin adapter. It is hard to screw this up as these are ATX standardized.

Good luck!

Thanks, that psu manual you posted is exactly the one I've got here but not all those cables are supplied for my particular model. Hence why I ordered an adapter from ebay.

You're overthinking this. These connectors work fine, I've used them for years. Just plug in one of the adapters you already have and be done with it.

A geek overthinking?? lol... nah.. never happens...

With the Corsair PSU's I have I get 2x8 pin cables, 1 of those 8 pin cables has 2x4 pin connectors, they can be used in a 8 pin MB connector or use just 1 4 pin connector for 4 pin MB connector.
I don't know what power cables your PSU comes with but check in the box and see if you have an 8 pin cable with 2x4 pin connectors on 1 end. You might even buy 1 from NewEgg or other PC stores. Oh and when in doubt, use all the connectors on the MB.

Thanks, but this 600W unit only has one 8 pin cpu connector.
When I look at the back of the PSU (pic supplied in OP) that 4 pin outlet below the 20 pin ATX mobo header is already used for the 24 pin mobo plug this board requires. I can get away with this without having to get another PSU by using adapters.

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You dont even need to use the connector. It probably wont even do anything for you at all.
Unless maybe you have an LN2 pot on the board we arent aware of.

That's what I though since purchasing this setup last year, but I now think... bugger it, just set it up & see what happens with OC adventures. There is an option in the bios to enable this header to "expand".

 

[WhitehawkEQ]

I was thinking something like this 8(4+4) spliter cable you could use both 4 pin connectors as 1 8 pin connector or just use 1 4 pin connector.

 

[EarthDog]

TL : DR - that connector is OPTIONAL, don't worry about it (especially with your CPU and you are only ambient overclocking).

Your manual should also say optional as well.

 

[trents]

You dont even need to use the connector. It probably wont even do anything for you at all.
Unless maybe you have an LN2 pot on the board we arent aware of.

This. Would only be needed in extreme overclocking scenarios not even possible with ambient cooling methods.

 

[Hotrod2go]

I can draw up to approx 200W according to HWinfo on the CPU/SOC package during CinebenchR20 multithreaded test @ 4.325Ghz with just the regular 8 pin connector.
But I stumbled upon this thread
& I'm not the only one with this curious aspect on their mobos.

So my understanding is it's only for extreme OC or for future cpus.

 

[trents]

Well, does the system run in a stable fashion without the extra 4 pin connector? Can you confirm?

 

[Zerileous]

One company did it and now everyone feels their board will look weak without it. A single 8-pin can push over 300W. Some manufacturers may configure their boards to require it though, but from a sheer power capacity standpoint it's entirely redundant/unnecessary.

 

[muzz]

I don't have a plug for the 4 pin, I just do without, no issues, but not using LN2 (and wouldn't use this board for that).