No. While it is possible to hide radio links inside any equipment it would still need an antenna and something nearby to communicate with. It would be obvious because of the antenna and the electrical power it would need to make communication. The chances of some 'secret' frequency that couldn't be observed making a link of long distances is absolute zero. Also consider that there is no space inside a CPU for a transmitter and if there was one it would interfere with normal operation and in any case most CPUs have metal casing which would shield the signal.
Tell us what actually happened to make you believe there is a security leak and we might be able to offer an alternative reason.
Brian.
By default a setting's values were something. After I installed an OS and drivers, I tested for several hours with the default settings. I shut down the computer at night, I didn't disconnect from power socket, I didn't turn off the main power switch. Next day I woke up and ran the tests, the settings's values were altered, no one had access to the computer while I slept. It was not connected to the Internet or anything which has access to Internet.
Your 2nd post is about CPUs, right? It seems possible what you say is true only for CPUs. What about motherboards?
If you have ever disassembled a USB WiFi adapter, you might have noticed that they don't have an extruding antenna, they either have a spiral or winding traces or Vivaldi type structure on their PCB, they are able to connect to 2.4GHz and 5GHz with these. For example:
Motherboards have many traces connected to microcontrollers, capacitors, etc, is it not possible to turn some traces into an antenna? Or some of them could have been designed with multipurpose to be able to transmit and receive data wirelessly. If something so small like above can transmit and receive data, how hard would it be to build something like that into motherboards and keep them secret?
Like for example the trace for audio signal on this motherboard:
It is the yellow trace on the lower left side, connected to a microchip and attached to capacitors, it is separate from other traces and equipment to avoid any noise interference, the trace is of the same width and size as the thin wire used as antennas in smartphones, with capacitors attached to them it could be made to send out an amplified signal.