PSU Confusion

I need some advice.

It is getting harder to know with certainty which PSU will work with a particular motherboard. There are now so many different combinations of power connectors classified as ATX.

I ordered a motherboard recently only to find that none of the connectors on the ATX power supplies I had on hand were an exact match. There are 20+4, 20+6, 24+4, 24+6, 24+8, 26+4, 26+6, 26+8. Yet, I believe all of these combinations are still called ATX. What gives with all the variety?

Is there some special code I should be looking for to determine compatibility before ordering? It gets expensive to order stuff that doesn't match, or it's a pain having to send stuff back.

Help! What am I missing?

BachOn

ATX is a standard, which there are different versions.

For the main power connector, the original used to be 20 pins, but most are 24 pins now (20+4 is exactly the same). For high draw processors, a separate power connector is required, which is either a 4 or 8 pin. Check your motherboard to see what connectors it has and buy the proper motherboard.

Generally speaking, if you get a power supply with a 24 pin main connector and 8 pin CPU connector, it will fit just about everything.

These don't exist and I have no idea where you see them (unless they are counting the PCIe connectors?): 20+6, 24+6, 26+4, 26+6, 26+8

Huh? 20+4 is the standard for desktop.

I think the PCIe plugs are part of the source for my confusion. I read the Wikipedia link you provided, Thideras. It helped. ATX is the form factor. But there are sub-varients of that. Guess I just haven't been keeping up. (But I'm willing to bet I'm not the only one.)

Here's the source of my mini-rant. I was trying to build a cheap box to use for a backup station. I bought an inexpensive motherboard/CPU combination from TigerDirect. Had RAM, drives, a case. Figured I'd just use an old PSU I had and I'd be good to go. But Nooooooo!

The MSI board had a 24 pin main connector slot and a 4 hole slot - I presume for CPU power (an AMD Athlon CPU). I already had a Power Supply that came with a 24 pin plug and a six pin connector. The mb had nboard video, so there was no need for an extra connector for a GRU on a backup station. Right?

The 4 hole slot on the motherboard has shapped holes the PSU connector must match. I said to myself - "Oh, this six pin connector doesn't match." So I bought one of those Molex to 4 pin connector adapters. When it arrived, the plastic connector holes didn't match the shape of the 4 pin port on the motherboard. The shape of the connectors was not the same.

So I went back to the six pin connector from the PSU. After experimenting, I found it would match the 4 pin port - with two of the pins not used. But I was concerned that this PSU wasn't a good match for the motherboard. So, I was looking to spend MORE money on another power supply. Good ones aren't cheaap. Cheap ones aren't good.

I've also seen motherboards with 24 pin connector ports. Some PSUs come with a 20 pin and a 4 pin that can be used together to come up with the 24 pins. Then there is a 8 pin connector.

I guess the bottom line is that I've got to do more homework before I buy. Generally, I order all my equipment for a new build at the same time. Now it looks like I'm going to have to get the motherboard first - then determine the power connector configuration needed before ordering the power supply.

Some vendors just say, for example, that a case comes with an ATX power supply. It's clear, there is more to it than that.

Sorry if this was a waste of bandwidth. I was just ticked that I've got to spend more money. "Bah, humbug!"

BachOn
(aka Scrooge)

A 6pin connector would be for a graphics card and should never plug into the CPU power connector unless you pushed hard.

May i ask why a PSU question is in the MEMORY SECTION? or in this case it does not matter! AJ. OOOPS!


Merry Xmas Thid!

Good catch, moved.

Sorry 'bout that. I must have clicked the wrong forum. Thanks, Thid! Mea culpa.