AT PC power supply only putting out 10V between 12+ and GND

[ben23]

i have a old 220w computer psu, so old that its an AT, and was built in '94, im using it to power my 12w x 2 amp that usually is in my school bag with the speakers, but im sick of charging the battery all the time at home, so i rigged it up to this PSU, but i measured the voltage between 12v+ and ground, and i only had about 10.5, dropping to 10.4 when pushing it. with no load its at 10.6
should i just get a new PSU? or is there something I can do

btw i hooked up the fan to the 12v supply but it couldnt be drawing that much, its only an 80mm fan.
its a regulated switching supply (well i assume its regulated), so shouldnt it be at 12v exactly?

btw I have 2 of the 12v+ twisted together and soldered to a wire going to the positive of my amp and 2 of the grounds twisted together soldered to a wire going to the negative, should i maybe just use one of each?
or diodes?

any help appreciated

 

[ante1]

Hi ben,

There are many types of PSU

 

[ben23]

yeah theres nuthing on the 5V rails, ill have to try that, i have a little 12v pilot light, ill measure the resistance and see if it will be ok, that way i can see if the PSU is on as well.

there is an orange "power good" wire, should i ground that or power that or anything, maybe so the PSU thinks the "power's good"
or is that so the MB knows that the power's stable
if i used the 12+ and 12- rails instead of 12+ and ground would it get more power?

 

[mvs sarma]

Ofcourse, ther is another way- if you don'et want to use 5V at all

the principal controll circuit regulating 5V, can be modded to control 12V instead of 5V. then the artifivial load on 5V can be avoided.


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