[ 1. The PSU fan is not turning.
  2. The +/- 12 volt lines on the motherboard are not on their own the cause of the PSU fan not running (but could be a second problem - multiple shorted caps).
  3. IBM 5150 with IBM 63 watt power supply. ]



Your computer is an IBM 5150 (PC), with genuine IBM 63 watt power supply.

The good thing about the IBM 63 watt power supply in the 5150 is that the Tandon full-height floppy drive alone is enough of a load to start/operate the power supply.
And so what we'll do now is do a very crude test of the IBM 63 watt power supply.

1. Turn off the power supply.

2. Disconnect both P8 and P9 from the motherboard.

p8_p9_removed.jpg


3. Connect the Tandon full-height floppy drive to the power supply.

psu_plus_floppy.jpg
Note that the pictured power supply is not
the IBM 63 watt one referred to by this procedure.

For some non-IBM power supplies, the Tandon drive
will not be enough of a load to start the power supply.


4. Turn on the power supply.


Click here if the power supply fan is now turning (continuously).

Click here if the power supply fan turned for a fraction of a second and then stopped.

Click here if the power supply fan is not turning.