Concern over "espionage devices" hidden in workstations sounds like something from prisonplanet.com.
Computer can do anything, connected to Internet, it is open to remote control and "data collection" - not a technical problem, just somebody wanting to do it. With the amount of circuitry crammed onto the chips, it would be surprise that it is not done.
Chinese at your computer control, Putin at the gas valve, suicider muSlimes roaming around, RATs crippling the US - long live "free" world.
Vote the bastRATs out into oblivion!!!
Any number of instructions can be easily burned into ROM at the time of manufacture. Even instructions that give a backdoor to the manufacturer to access the computer over a network.