20 pin psu to 24 pin motherboard

[nfinity]

The psu spec
400Watt
5v = 30A
12v = 25A
3.3v = 28A

I was going to use an extra 4pin from a dead 24pin psu and use two extra cables from the 400watt psu to get the 12v 5v 3.3v and ground I need extra to go to that 4 pin.

This should easily be doable right? thinking this 775 motherboard and other hardware won't draw more then 150watts total. 35w cpu, 2GB ddr2 memory, dvd drive and 2 hard drives. that is all it has to power.

 

[bchur83]

The 20 pin will work just fine as long as you arent overloading the 400W PSU. It doesnt require the extra 4 pins to work. As for that 400W PSU, it has a big 5v rail, so it isnt optimal for a newer 775 system. Most of the newer systems like the 12v to be bigger. It should work though, just not optimal.

 

[Bobnova]

What make/model PSU, and what CPU/GPU?

You can use a 20pin PSU in a 24pin motherboard without modifying anything, but if the PSU can't handle the parts it won't matter much.

 

[nfinity]

The 20 pin will work just fine as long as you arent overloading the 400W PSU. It doesnt require the extra 4 pins to work. As for that 400W PSU, it has a big 5v rail, so it isnt optimal for a newer 775 system. Most of the newer systems like the 12v to be bigger. It should work though, just not optimal.

So your saying I don’t need the 4pin in the motherboard. So plugging in the 20pin from the psu into the 24 pin motherboard will work by its self without modding? I see how 30a for the 5v is way more than enough and older psu were geared more for that. But 25a for a 12v rail I would think is still fine for what I’m doing… right. My more modern dell machine has a 300watt psu 18a 12v and it has a 24pin motherboard.

By the way, this is the motherboard if it matters..
Jetway I31GM4

 

[nfinity]

What make/model PSU, and what CPU/GPU?

You can use a 20pin PSU in a 24pin motherboard without modifying anything, but if the PSU can't handle the parts it won't matter much.

I didn't know that


powmax lp-8800d psu…. I know… not the best
Jetway I31GM4 motherboard
Celeron 450 – 35watt
Dvd player and 1 or 2 hard drives

 

[Bobnova]

Not so much not the best as fairly terrible.
However, if it's just running a 35w CPU and using onboard graphics, it should be up to the task.

 

[nfinity]

Not so much not the best as fairly terrible.
However, if it's just running a 35w CPU and using onboard graphics, it should be up to the task.

Yeah, I wouldn't want to use more then half the watts this psu says it can put out. assuming under load I should be around 150ish for watts required.


So your positive I don't need power sent to those extra 4 pins on this motherboard? It just feels weird leaving them empty.

 

[Bobnova]

Yup, positive.
You'll be fine, assuming the PSU doesn't decide to explode.

 

[nfinity]

Yup, positive.
You'll be fine, assuming the PSU doesn't decide to explode.

well, if the psu exploded I wouldn't care, but if it took out my motherboard or anything else, I may be a bit upset but I basically got all the parts for $30 so not a huge loss.

thanks for the advise