Low voltage wire & electrical wire (NM)
This question comes up a lot.
For a worst case and simple experiment run several yards of all three cables together, while pulling 10A through the Romex by running a hair dryer on the end. Motors with brushes like in a hair dryer put out all kinds of nasty wideband interference, which you can hear on an AM radio.
The Romex will put out a magnetic field which really can't be shielded against so I'm depending on the 60 Hz being so far removed from the frequencies going through the other cables.
Also, computer stuff has error-correcting methods, which you would notice as a slowing down if the computer were detecting errors.
IMO you won't notice anything.
If you do want to shield the cables from the Romex you need to use a section of steel/iron pipe, not copper. If you want to go really hi-tech, use mu-metal.
Last edited by Yoyizit; 05-04-2010 at 05:11 PM.