Risks of using ATX psu with ATX 2 motherboard ?

[Admiral]

Google doesn't seem to be my friend on this issue and my skills on searching MURC are a bit rusty, so I remembered reading here that you risk damaging the motherboard in time with this combination.

Could someone elaborate an maybe explain if there are any other risks for the CPU, video card ?

[gt40]

I believe the atx-2 spec specifies a minimum of 720ma on the 5v stanby line (pin 9)
If the power supply cannot deliver this, there may be problems with powering up, or damage to the power supply.

[Admiral]

edit

hmm, +5VSB:

min load 0A
max load 2.0A

it's an Antec 550w True Power (older ATX 1 model)

[Gurm]

ATX 2.0 is more of a MINIMUM specification than anything. So even piss-poor PSU's must come up to a certain standard. Good PSU's are already that good.

But you will need an adapter.

[Admiral]

adapter, can't I just plug it in and leave the other 4 pins on the motherboard unused ?

[Admiral]

So the adapter actually splits power from +5, +12V... and supplyies it to the extra (PCI-E) 4 pins on the motherboard ?

[az]

AFAIK the extra 4 pins only provide additional lines to lower resistance. This is only necessary for systems with a very high power draw.

Look it up before rushing out to buy something; I am sure you can just leave the extra pins unconnected.

[gt40]

I beleieve AZ is correct - my Asus mobo manual has the connector marked as 'optional'

[Wombat]

I beleieve AZ is correct - my Asus mobo manual has the connector marked as 'optional'

My DFI says that you're likely to experience instability if this connector is not fed.

[az]

Yes, because the higher resistance may cause the line voltage to sag a little, especially when under heavy load. I've read several reviews now that say the additional pins are only necessary for systems with a high current draw.

[Marshmallowman]

And on some systems its mandatory, most dual opterons boards..etc