"Steve Bonine" wrote ...
Jack VK2CJC wrote:

If its a stray RF problem, which I am very willing to accept, I'm
surprised that it effects two very differently designed computers in
exactly the same way.

Do they perhaps have the same CPU chip, in spite of their very
different design?

Not the CPU's fault. It is almost guaranteed to be the "brick"
power supply. Note that the problem goes away when you
disconnect the "brick" and run on the internal battery supply.

I bought a used "brick" power supply for this Dell laptop on
eBay and it came with an intermittent (3-pin U-ground) mains
power plug. So I chopped it off and replaced it with an after-
market, 2-prong plug and I don't have problems with ground
loops and RFI from the garbage power supply anymore.

Yeah, yeah, green-wire "protective ground", etc. etc. Well,
I don't see what exactly the "protection" here is doing, and
if the green-wire ground WAS supposed to be there for RFI
shielding purposes, then why does it *go away* when I
disconnect the green-wire ground? Riddle me that! :-)