whining sound from engine
 

i have a whining sound that only seems to appear after some spirited driving or sat at speed on the motorway etc
if i keep below 3k i dont get the problem. sounds like a bearing noise and it increases with engine speed, still there when stationary and with the clutch in or out.
i got a feeling its either the alternator or the power steering pump.
eiher of these s a common problem ??
any ideas on how to try and diagnose the culprit ??
car is a turbo wagon my98 with 115k miles.
all oil levels ok

Penny to a pound says power steering fluid. Top the level up to 'hot max' (ie well over the cold max mark) and see if it helps.

i get that as well. Only after a "spirited" drive.
Sounds "belty" if you know what i mean.

power steering levels ok, the fluid was changed not that long ago either according to the service history