20 pin t0 24 pin MB...

[casey]

I was just wondering if you must have the 20 to 24 pin converters to hook up a 20 pin power supply to a 24 pin MB. I haven'r run into this problem yet but noticed I have some power supplies on the shelf with 20 pin power cables. I just thought if I need converters maybe I should get them before hand. These are older PSU's but all of them over 400 watts.

[Dan18960]

A good reason NOT to have a stock of parts that can become obsolete.

I think you might as well dwindle those power supplies down and replace with the new 24 pin models.

[casey]

Dan, I agree but you didn't answer the question...

[Seth]

I was just wondering if you must have the 20 to 24 pin converters to hook up a 20 pin power supply to a 24 pin MB.

Yes, you need the adapter. The psu will work fine provided that the wattage and amperage are sufficient.

[casey]

Thanks Seth, That's what I wanted to know as I haven't run across this problem yet...

[Seth]

Thanks Seth, That's what I wanted to know as I haven't run across this problem yet...

No prob. A couple of other things that warrant consideration:

1) Be carefull if the old psu's don't say ATX, as they may not comply to the ATX voltage/color standards.

2) The mobo and/or psu may or may not have a connection for the cpu supply voltage. Also, the cpu supply voltage can differ as well. Are you familiar with that connection?

[casey]

The mobo and/or psu may or may not have a connection for the cpu supply voltage. Also, the cpu supply voltage can differ as well. Are you familiar with that connection?

No Not really. These power supplies are probably a year old and have the extra 4 pin connection that goes on the motherboard separately from the power connection. I really don't know what you mean when you say CPU supply voltage..

[Seth]

That's the one I was talking about Casey.

If the mobo requires it, but the psu doesn't have it, you can buy an adapter that will hook up to a peripheral connector on the psu.

[casey]

Thanks Seth,,

I'll try and get to a computer show to get what I need for the Power supplies...

[athomsfere]

I just want to add;

The adapter works, its not a very good idea though.
For anything but the BEST ATX PSUs the power provided isn't enough, and you could easily take out the PSU and other components.

What happens is you split the rails, mostly the 12v. So 12v at 18a (A pretty mis range no thrills motherboard) becomes a 12v at 9a (Enough to underpower about any board that takes a 24pin ATX or an ATX 2.0 board)

If you have to use the adapter for the PSU, I wouldn't use it for anything more then a test bed PSU.

[Seth]

I just want to add;

The adapter works, its not a very good idea though.
For anything but the BEST ATX PSUs the power provided isn't enough, and you could easily take out the PSU and other components.

What happens is you split the rails, mostly the 12v. So 12v at 18a (A pretty mis range no thrills motherboard) becomes a 12v at 9a (Enough to underpower about any board that takes a 24pin ATX or an ATX 2.0 board).

Thanks for that info athomsfere. Something doesn't seem to add up though. I mean really, how much more amperage could a 24 pin board require over a 20 pin? Also, it's not the mobo that's going to draw most of the amperage, it's the components. So it's going to depend on the specific amperage draw of the ide and usb devices, type of video card, etc.

I do see your concern however. If the psu is overworked and blows, it could easily render the computer a door stop.

[athomsfere]

Thats where dual 12v rails come into their own in the ATX 2.0 and up standards.

it's not the mobo that's going to draw most of the amperage, it's the components. So it's going to depend on the specific amperage draw of the ide and usb devices, type of video card, etc.

Again, nail on the head. Assuming all the components are low draw, everything would be fine. Most boards for the 24 pin PSU use pretty heavy duty components. A great example would be the difference in certain 939 systems.
An Athlon 64 3200 Venice is pretty low draw, especially with C&Q enabled and the average user with lets say an old AGP Nvidia 5200.
If it were a X2 processor and a 7900GT PCIe card though (An extreme I know) the adapter is not going to be a good idea.

Honestly there are two choices, listing all the parts by draw and rails, or playing it safe and getting a decent PSU.

My PSU is 480w with dual 12v rails at 19a each, I chose it beacause I knew my draw is on average high (Run up to 5 HD, 2 opticals, and an overcloced CPU and RAM) I just want to risk it.

[Seth]

Honestly there are two choices, listing all the parts by draw and rails, or playing it safe and getting a decent PSU.

I think that's the best advice.

[casey]

Just to finish up with the 20 to 24 pin power supply connectors: I managed to get to the computer show in Allentown yesterday and like last month was really disappointed. I went with the intention of getting a couple of adaptors for the power supply and another ergonomic Microsoft keyboard, which I find I am so use to that it's hard to use a regular keyboard. To make it short the few stands that were there didn't have the adaptoir for the power supply or the microsoft ergonomic keyboard. What i did find out as I changed the Antec case that had my 64x 754 AMD 3000 processor was that the MSI motherboard and the Antec case only had a 20 pin connector. I had to change the power supply to install the Asus motherboard running my AMD Opteron. So now I end up with another 20 pin power supply from the Antec case. I guess it's no big problem as I figure we have at least 20 computers in the family that have the 20 pin connectors...

[mylanta]

Larry,
You are lookking for trouble with 24 pin adapters and several motherboard makers have warnings o their sites about doing that. Use a 24 pin with a 24 pin motherboard.

[athomsfere]

Larry,
You are lookking for trouble with 24 pin adapters and several motherboard makers have warnings o their sites about doing that. Use a 24 pin with a 24 pin motherboard.

Again, I agree.

I wouldn't risk it, just get a good PSU.