The problem you describe above sounds like a PSU issue. An onsite tech would have the option of checking that out with a multimeter.
We all had to start out somewhere. The guys at Tier 1 support(whether it is support within your company or a vendor like Dell, HP, etc.) have to "learn the ropes" before they can move up to Tier 2 or higher. Nobody came into the IT field knowing everything (despite what they may tell you about their certs...) It takes time and effort to gain knowledge in this business.
Be that as it may, it IS a pain when you're a level/tier 3 tech talking to Dell tier 1 when troubleshooting a system. If you're worth your salt, you'll have already gone through all the troubleshooting steps before you call their tech support line. It is especially frustrating when the first answer to everything is "re-image the machine." It is reminiscint of the "did you reboot" answer most help desk techs will give.
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