Solved! Seasonic M12II EVO (520W) for a GIGA-BYTE Z390 UD m/board -- Q about 4-pin ATX 12V power connector

[DodgerLD]

I have an existing Seasonic M12II EVO (520W) PSU and I'm considering purchasing a GIGA-BYTE Z390 UD m/board – will it work? How do I connect the 4-pin ATX 12V power connector? Is the PSU missing that?

 

[DodgerLD]

Judging by the replies here and here, it sounds like this connection is unnecessary in many cases.

I'm just going to get an i5-9400F, so I think it should be fine.

 

[UsandThem]

You are correct.

That extra 4-pin CPU connector is just for people who are heavily overclocking a demanding CPU (like the 9900K).

You shouldn't need to plug that in with a 9400F.

 

[mindless1]

Each pin of the connector is capable of 6A, but on the 4 pin, only two are power (and two ground), so 12A @ 12V = 144W. Thus, since manufacturers round off TDP for CPUs, a 4 pin supports up to 140W CPU.

i5-9400F is only 65W TDP, so you could even o'c it a fair amount before you hit the ceiling of 144W, though personally I'd prefer to stay with 90W or lower CPUs with only a 4 pin connector. More margin more good.

How do I connect the 4-pin ATX 12V power connector? Is the PSU missing that?

Judging by the replies here and here, it sounds like this connection is unnecessary in many cases.

You connect it where it plugs in, is keyed to only fit one way. You either have a 4 pin connector or 8 pin. If you have the 8 pin you don't need the 4 pin, or if you have the 4 pin you don't need the 8 pin unless your CPU is more than 144W TDP.

 

[DodgerLD]

Thanks for the replies, I appreciate it.

 

[JEDIYoda]

anytime!!