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I'm thinking about making a small custom-build server. It would only use around 60W maximum. I don't want to pay too much so I think using an old power supply would work.

The motherboard I'm thinking about to buy has a 4-pin CPU power connector and 24-pin ATX power connector. The old power supply has multiple power outputs for the motherboard including a 20-pin ATX power connector and a 4-pin connector that was also used in the old computer to power the CPU.

Can I just plug the 20-pin power connector in the 24-pin connector of the motherboard and connect the CPU power supply? I don't know if I need to plug the 4-pin into the extra 4 pins of the 24-pin connector, leave it unplugged or use the 4-pin connector on the MB for it.

I also assume a 250W power supply won't damage anything and will power it even if it's only using 10W? Or does it need a minimum output?

I've already searched but I couldn't find a specific question about using the extra 4-pin connector.

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marked as duplicate by Ƭᴇcʜιᴇ007, Shekhar, Dave M, Breakthrough, Carl B Oct 2 '13 at 6:24

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

up vote 1 down vote accepted

I would definitely check out those links that techie007 included, however given your use case I don't think this is an exact duplicate of any of those questions.

Your motherboard should work with only 20 pins plugged in. It's not ideal and I can't say it will work with 100% accuracy but if it's a well designed motherboard it will work. With that said, adapters from 20-24 pins are pretty cheap and plentiful.

Your second question about damaging your system with a power supply larger than needed is easy. No it will not damage your computer, you could plug in a 1200W power supply and it would be fine. The wattage on the power supply is the maximum power it can deliver but it can deliver any amount of power less than it's maximum safely. For example, your 250W power supply can actually deliver anything from 1-250W of power, since your 60W is in that range you'll be find.

Welcome to superuser!

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Thank you for your answer. – Randomguy94 Sep 28 '13 at 19:42

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