Just buy a very LOW WATTAGE slim factor( Chinese mobile phone technology ) tiny computer and screen/ tablet with no hard drive or fan. Only use SSDs. NO ORDINARY HARD DRIVES. 12vDC motors are the dirtiest things ever for magnetic and FRI pollutions. Sellers should have to put the wattage of devices on the specs.
My monitor 22" is less than 10 watts but they don't make them that energy efficient any more cos they think bigger and hotter is better and we cannot choose cos they don't tell us this info..Cheap AM radios are best for showing emissions. Never be within the range you can pick up as a fuzzed mess. Use wired every thing with ferrite chokes. I only use 12vDC from a linear power supply. Avoid 5v USB as this is harder to get clean because of pulsed chipped transformers power supplies. Who decided on 5 volts? Why not 6? Sadly most USB devices cannot handle 6 volts.
If anyone has found a 12vDC low wattage monitor please tell me PLEASE? Mine needs replacing.