I've always wondered, what is the purpose of those metal shields that come preinstalled to cover up the empty 5.25" drive bays (behind the plastic covers).

Are they supposed to keep harmful radiation away from my sensitive knees? Are they necessary?

Most likely they are EMI shields. No they're not absolutely necessary, although their removal may increase interference if a TV/monitor/radio/other electronic device is close. (not very likely, but possible)

I doubt your knees would notice.

Mike.

technicaly your computer is supposed to be completely surrounded by metal.

this is my boomstick!

Funny you should ask: Those EMI shields are meant to make the case FCC compliant, but here's the funny part: most cases with windows also have them, and the window defeats the purpose of the bay shields!

Most cases with windows are not FCC compliant, of course compliance depends on what hardware you put into the case.

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Yeah I figured FCC compliance was the goal, but if windowed computers aren't FCC compliant anyways, I guess you don't have to be FCC compliant to sell a computer? Apparently FCC compliance is just an optional feature to help sales?

The FCC compliance is too make sure that if you buy a case that isn't, you should know you could disrupt radio traffic. It's not illegal to sell or use these cases, but if they cause interference, you're the one responsible.

Ahh, addiarmadar says that their purpose is to help ward off klingon attacks. OOOO MYYY.

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It's a funny thing. First of all, cases are usually made in a manner that would make the system FCC compliant (cases themselves aren't FCC compliant or uncompliant because the machine doesn't cause interference until you put parts into it).

Then windows are added. So the same case that originally would have resulted in an FCC compliant PC is modified after the original design, in a manner that makes them no longer able to hold the parts you add compliant.

So you can buy any case you want, but when you build the system, you'll be responsible should the system interfere with radio.

Now, if you're a major manufacturer, you have another FCC problem: If you sell a complete computer to someone and it interferes with their radio, you're the one financially responsible for selling a "defective" device. As far as I know, they could return the system for a full refund. That's why companies like Dell make systems in boring looking cases. That's why clear Macs had the full shield underneath the plastic.

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<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>

I hear that are to help the case keep its shape during manufacturing. That way the corners stay 90 degrees.

I belive the FCC simply require that devices don't cause interference, I don't think the have specific rules regarding cases, just complete PC's.

Otherwise transparent cases and window cases would be illegal to sell.