computer power supply question

[GTB_an_Owl]

One for the techies

i have recently bought 4 new 500wt power supplies from 3 different dealers at the local computer fairs here on the coast (3 different brands)

ALL 4 OF THEM HAVE NO -5 volt rail when i put them on my power supply tester (i have checked an older power supply with the tester and it shows a reading on -5 volts)

QUESTION!

have i just been unlucky - or have they taken the -5 volt rail out of the latest power supplies?

this might just be up your alley Gary!

geoff

[supernova1965]

I don't think the -5 is used much anymore older MAC machines use it for the power light I think you are fine it is not needed if I am wrong I am sure someone will say so :P

[AdrianF]

Just looked at my spare 1200w pc supply and no it does not have -5v

Adrian

[GTB_an_Owl]

it would appear that pin 20 on the 24 pin connector is the -5 volt supply.

i have just built a new system (well new bits and old bits) and used one of the "faulty" power supplies

ALL WORKS WELL

so i guess the answer to my question has been mostly solved

-5 volt is not needed (anymore)

geoff

[technofetishism]

Bit further than not needed anymore, Prohibited in the ATX12V standard since 2003 :) (1.3 and 2.0 versions)