Computerland AT power supply dead

[falter]

Got an AT power supply from a Computerland machine.. it does not put out any power whatsoever when plugged in and turned on. Fuse looks fine.. what would be the next thing to look at?

Many thanks!

 

[tradde]

Does it need a load? Does it require a signal from the motherboard? Just guessing here.

 

[falter]

I don't think so. I think ATX requires those things but as far as I can recall AT turns on the moment you throw rhe switch. I'm not even getting the fan turning.

 

[modem7]

...but as far as I can recall AT turns on the moment you throw the switch.

Some will require an adequate load.

I'm not even getting the fan turning.

Is the fan AC or DC powered ?

 

[falter]

I pulled the PSU out of my BC88, which is apart from CPU card the exact same machine. The PSU does power up without load. Not sure but I think following the wire the fan is DC powered.

 

[modem7]

Not sure but I think following the wire the fan is DC powered.

If the power supply is not producing DC power, and the fan requires DC power, ...

At switch-on of the PSU, does the DC powered fan turn just a fraction? Some (repeat: some) fully functional PSU's will do that if:
* PSU is overloaded by something; or
* PSU is underloaded, i.e. PSU of a type that requires adequate loading, and no adequate load present.

I pulled the PSU out of my BC88, which is apart from CPU card the exact same machine. The PSU does power up without load.

Like IBM, Computerland may have sourced the PSU's from different makers (same case - different 'guts'). If that is the case, then some Computerland PSU's may require adequate loading.

You have not indicated whether or not you tried the 'problem' PSU in the BC88.