Question PSU with 8 pin and 4 pin CPU power plugs?

[Beretdude]

I just bought a new mobo, but it requires an 8 pin and a 4 pin plug, for cpu power. 2 existing psu's, that I have, do not have that. How do you find the right psu? This is for an MSI Z490 Carbon Gaming mobo.

 

[jonnyguru]

Typically, the PSU will have two 4+4-pin cables. What that means is it's a connector that can be used as an 8-pin or a 4-pin (by splitting the 8-pins into two).

99% of the time, though. You don't actually NEED both connectors plugged in. Usually the motherboard functions perfectly with just the 8-pin connected. You'd have to have a very high end CPU or a very overclocked CPU in order to actually NEED both connections populated.

Usually you only see very high wattage PSUs with two CPU power connectors. Off the top of my head, there's the Corsair Vengeance 650M, Corsair RM650, Corsair RM850x, Corsair HX750, Corsair HX750i and Corsair AX850 (because I have all the Corsair PSUs memorized. 😀)

 

[Beretdude]

Typically, the PSU will have two 4+4-pin cables. What that means is it's a connector that can be used as an 8-pin or a 4-pin (by splitting the 8-pins into two).

99% of the time, though. You don't actually NEED both connectors plugged in. Usually the motherboard functions perfectly with just the 8-pin connected. You'd have to have a very high end CPU or a very overclocked CPU in order to actually NEED both connections populated.

Usually you only see very high wattage PSUs with two CPU power connectors. Off the top of my head, there's the Corsair Vengeance 650M, Corsair RM650, Corsair RM850x, Corsair HX750, Corsair HX750i and Corsair AX850 (because I have all the Corsair PSUs memorized. 😀)

I think this might be that 1% of the time, when I might need it. I tried installing windows on it, but about halfway into the new install, the computer shut down. It continues to shut down now. I did couple the 2 4x4's together, to make the 8 pin. Would it be possible for me to alter a plug for the PCI, and whittle it down to 4 pins? It appears that I just need 2x +12 v and 2x -negatives.

 

[jonnyguru]

I think this might be that 1% of the time, when I might need it. I tried installing windows on it, but about halfway into the new install, the computer shut down. It continues to shut down now. I did couple the 2 4x4's together, to make the 8 pin. Would it be possible for me to alter a plug for the PCI, and whittle it down to 4 pins? It appears that I just need 2x +12 v and 2x -negatives.

List all of your hardware. It's highly unlikely that your issue is because you don't have both CPU power connectors connected if it's rebooting simply trying to install Windows.

 

[Zerk2012]

I'm not sure if this has changed or what since the 10900K can pull into the 240 watt area under turbo mode.

Just bought a new motherboard ( your words) what processor are you trying to use.

The Z490 boards only support the new processors.

https://www.msi.com/Motherboard/support/MPG-Z490-GAMING-CARBON-WIFI#support-cpu

 

[Beretdude]

List all of your hardware. It's highly unlikely that your issue is because you don't have both CPU power connectors connected if it's rebooting simply trying to install Windows.

Mobo........... MSI MPG Z490 Gaming Carbon WiFi Gaming

CPU............. Intel Core i7-10700 Desktop Processor 8 Cores up to 4.8 GHz LGA 1200 (Intel 400 Series chipset) 65W

Memory..... Corsair Vengeance LPX 32GB (2x16GB) 3200MHz C16 DDR4 DRAM

PSU........... Corsair TX 750 watt (13 years old, but runs quiet)

HD.............. Seagate 2TB SSD 2.5 Inch SATA 6GB/s Flash Accelerated for Gaming PC Laptop

I originally tried to install, with the graphics card that I had. Immediately I was told my card would not cut it. So, I removed card, and attempted to install windows...it started...it downloaded and started installing files from USB, then shut down.

 

[jonnyguru]

13 year old PSU, eh?

That might not have very strong voltages any more. Do you have a DMM you can plug into one of the available connectors to see how low it is.


You know what... screw it. Replace the PSU.

You have a $300 CPU. A $300 motherboard.

And you can't be bothered to use a PSU made in the last decade?

 

[Beretdude]

13 year old PSU, eh?

That might not have very strong voltages any more. Do you have a DMM you can plug into one of the available connectors to see how low it is.


You know what... screw it. Replace the PSU.

You have a $300 CPU. A $300 motherboard.

And you can't be bothered to use a PSU made in the last decade?

Thanks, mate. I guess, me being old myself, I thought I would try to hold onto something from the last build, so I didn't order a new PSU. Guess I will get that, AND a graphics card. Again, thanks for your help.

 

[Beretdude]

Thanks, mate. I guess, me being old myself, I thought I would try to hold onto something from the last build, so I didn't order a new PSU. Guess I will get that, AND a graphics card. Again, thanks for your help.

Just to complete this thread. First, I want to thank all of you, for your help. I did end up getting a new PSU, and a graphics card. After some initial hiccups, I got all working nicely. A bit disappointed that it takes so long to boot up, and shut down, but otherwise, pretty fast.
Again, thank you all.