My computer lights up and turns on but nothing happens, why?

By Leo Notenboom

I’m having problem starting up my computer. When I press the Power button, it lights up and everything inside it runs, but nothing appears on my monitor. I don’t know what’s the problem. I already cleaned it and had reset the CMOS, but nothing works.

Well, I’ll put it this way: just because the lights are on, doesn’t mean anyone’s home.

I get this and similar questions often. You turn on your computer. It makes noise, you can see lights – perhaps even blinking lights – and assume that it must be running.

It might be.

Problem is – it might also not be running at all.

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Lights and noise mean … nothing, really

The phrase “everything inside it runs” is actually impossible to prove just by looking.

You might very well hear the fans all start to blow, disks might start to spin, and you might see some lights come on, but about the only thing that you can say by all of that happening is that the computer has power.

“…don’t read too much into blinking lights, spinning disks, and running fans.”
I’ll put it another way; if you actually removed the CPU or the RAM (don’t), the fans would blow, the disks would spin, and some lights would come on.

And the computer would have exactly zero chance of actually working.

So don’t read too much into blinking lights, spinning disks, and running fans.

The good news is that the computer appears to have power. The bad news is that you simply can’t assuming anything more.

Article Continued Here

This post is excerpted with permission from Leo Notenboom.

About Leo Notenboom

Leo A. Notenboom is the owner of Puget Sound Software, LLC and the Leo in Ask Leo!. Leo has been in the personal computer and software industry since 1979, as a software engineer, a manager of software engineers, and as a consultant. In 1983 Leo joined what was then a medium sized local company called Microsoft and spent the next 18 years in a wide variety of groups working on a wide variety of software. If you're running Microsoft Windows, if you've used a Microsoft development tool or Microsoft Money, or if you've ever purchased a ticket through Expedia, there's a good chance you've been touched by some of his work. And of course, since 2003, Leo has been answering your tech questions on Ask Leo!

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