After seeing my power steerin light come on (hasn't again so far) I'm probably just paranoid but I've noticed that when dry turning when not moving or at slow speeds I can hear a whirring noise.

Normal? :-)

I can hear mine at parking speeds if the radio is off, or if I hold it on full lock.

Although I dunno what state of health mine is in after a garage clamped the hyrdolic pipes and sent me off home in it.

But I think its always done it even before it was butchered.

Normal in most conditions.