No matter which pc they send me for my store it errors no boot device

I am a store manager, and have to work on a pc hooked to corporate in order to handle daily operations. Last week, I went in to find my pc with a black screen “no device to boot to". I restarted, and it gave me 3f0 error. When I called corporate for support they sent me another PC. Got it, and the same error displayed on start up. Called again, and they sent me another! This one flashed red and beeped, but did not come on. On the off chance the original healed I tried it again, and it booted up. Worked 2 days, and today shut down while I was in conference with an employee. Just went to shutting down page. Now it is 3f0. So three different computers… same cords. Can they do this? I do not have administrator access . Suggestions??? I am at a complete loss!