What exactly is the "power steering pump soon-to-die noise"?

Mine buzzes lightly, and increases in pitch if I turn the wheel. I only notice it in the garage, or if I pull up to a wall with the windows open.

I asked in the power steering problems thread, but got nothing, so imma try again.

 

when I had a brand new one installed it made no noise at all... for a couple weeks, then it was right back to the relatively quiet buzz. if this were a belt driven pump that noise would for sure be bad, but I think the electric motor in these is just noisy... probably not a bad noise.