I would think the dominant noise in a computer is
the multiple clocks, their harmonics, and their
mixing products - very nasty. It is the reason that
building WLAN and Bluetooth into computers has been
so difficult. So AWGN probably pales in comparison.
In other words, the dominant noise in a computer
chassis is not white noise (random) at all, but
This might be of use.
Also, search on the NIST website for specifically
what you're looking for. Our tax dollars have funded
a lot ofresearch on the topic.