[Rd] Whine in dual core Windows PC if R uses full CPU capacity

[elw at stderr.org]

> I think I've only come across it a couple of times, and didn't have any 
> replication, so I don't know if they were unusual individuals or a 
> design problem.  From your description of replacing the mb, it sounds as 
> though it's a design problem -- unless as Uwe suggested, it's a power 
> supply or some other part that you didn't replace.

I've seen this kind of resonance problem before, in a couple of different 
computers with a couple of different mixes of hardware.

What usually comes out, eventually, is that some part in your system is 
very poorly shielded and ends up reacting badly to other sorts of activity 
in the system.

I've seen both video cards and audio boards involved in this kind of 
problem, as well as the more sterotypical "dirty" power supply or 
third-rate motherboard design.  I've also seen spurious current applied to 
the expansion bus [by a functional, but marginal card] cause very similar 
issues.

The only way to *really* trace down the problem is to swap the parts in 
the machine for other, known-non-problematic parts.  This is expensive, 
and takes a lot of time.

--elijah