Interesting; I guess it behaves a little differently with capacitative loads versus just resistive loads. But, at least it confirms (without involving the motherboard) that the supply is indeed not working, which was the only real purpose of that test anyways. Unfortunately, the test is not further diagnostic in any way, it just removes the motherboard as a variable.
Hopefully for consistency the known good supply works with your test rig, just to confirm that it's all set up properly?
Hopefully for consistency the known good supply works with your test rig, just to confirm that it's all set up properly?