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Do PCs need a case?

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Cobalt60

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Im just wondering if the case of a personal computer shields the user from any potentially harmful radiation. I am one of those people who do believe that cell phones and wireless networks can potentially cause health problems. With that in mind, do I need sheet metal between me and my 4.5GHz CPU? Or any other component in my super powerful PC?

Thanks

-Chris P
 
I dont know about that but these people made an interesting case for their PC **broken link removed**
 
Cell phones are designed to optimally radiate their power into the environment intentionally. PC's are not. The only risk is under extremely close contact with an intentional radiator. Even a few feet away from a PC is a thousand times or more better than a few inches away from a cell phone. And there is very little data to substantiate risks from cell phones unless you're using one constantly under high power. A typical cell phone user does not fit this case, and even those will have other environmental health risks that so far overshadow cell phones as a risk to early death as to make it a waste of your time to even think about it.
 
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You receive higher doses of radiation from X-rays at the dentist than your computer. You receive higher doses of electromagnetic radiation from the power lines in the walls of your home. The electrons that bombarded you for years from CRTs on televisions and older computer monitors subject you to more.

The ground under your home radiates NORM (Google the term) at potentially dangerous doses in some cases from natural sources.

You are exposed to equally high if not higher doses of radiation from the circuits in your car every time you drive. If you use natural gas, you are exposed to radiation. Our bodies are bombarded with microwatts of RF energy from high frequency global radio transmissions and local VHF/UHF/microwave across the spectrum. Pulsars, novas, and solar flares in space are blasting us with x-rays and microwaves 24/7/365.

Now, to put this in perspective...computer circuits rely on comparitively low RF energy to operate. The reactive circuits involved tend to be more voltage dependent than current consuming. There are chokes and coils but not like a radio transmitter, and not at very high power levels. The fields a computer creates are probably more electric than magnetic.

The case of your computer is shielded in most cases. And this "does" have the added benefit of protecting you from radiation but the primary concern is protecting the computer from interference and not interfering with other devices.
 
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You're a HAM ke5frf?

Have you ever tried snooping the SVGA signal from a video card? The pixel clock and sync pulses etc are all generated at the same ??Mhz rate xtal locked, would it be possible to tune to that frequency and receive someones video card signal?
 
I am one of those people who do believe that cell phones and wireless networks can potentially cause health problems. With that in mind, do I need sheet metal between me and my 4.5GHz CPU?
Yes it's all very dangerous! That's why I'd suggest that you use a protective helmet like this one

**broken link removed**.

I find it also protects me from the government.
 
Im just wondering if the case of a personal computer shields the user from any potentially harmful radiation. I am one of those people who do believe that cell phones and wireless networks can potentially cause health problems. With that in mind, do I need sheet metal between me and my 4.5GHz CPU? Or any other component in my super powerful PC?

Thanks

-Chris P

Your question is based on the assumption that I also believe as you do, and that as a result of this I know how much radiation is too much and how little is little enough. But since I don't believe as you do, I find it impossible to answer your question. In the absence of facts on which to base a judgment, the various regulatory agencies worldwide are playing it safe by regulating maximum RF safe levels that we can be exposed to. Those levels are considerably higher than the typical radiation from a PC with its case closed. However, if you believe that radiation from cellphones and wireless networks is harmful, then you must also believe that radiation from a PC is harmful, and in that case we have a problem because it is not possible to eliminate all RF radiation from your PC without shutting it off completely. So, it is entirely a matter of degree. How much is too much? It is a matter of your opinion.
 
Those levels are considerably higher than the typical radiation from a PC with its case closed. However, if you believe that radiation from cellphones and wireless networks is harmful, then you must also believe that radiation from a PC is harmful, and in that case we have a problem because it is not possible to eliminate all RF radiation from your PC without shutting it off completely. So, it is entirely a matter of degree. How much is too much? It is a matter of your opinion.

I did not say I believe the radiation is harmful. I said I believe it is POTENTIALLY harmful. Cell phones have only been in widespread use for what, 10 years? So theres no example to show what happens after, say, 20 years of cell phone use.

At any rate, I feel that a PC is a somewhat unique example in that its CPU is operating above 4GHz. Im not too familiar with other items that operate at such a frequency, even most PCs dont operate that fast.

The degree of exposure thats acceptable can be compared in relative terms. For example, I use a cell phone, but perhaps only a couple minutes a day. So, how would sitting in front of my 4.5GHz CPU, with no case around it, for a period of several hours a day, compare?
 
I did not say I believe the radiation is harmful. I said I believe it is POTENTIALLY harmful. Cell phones have only been in widespread use for what, 10 years? So theres no example to show what happens after, say, 20 years of cell phone use.

At any rate, I feel that a PC is a somewhat unique example in that its CPU is operating above 4GHz. Im not too familiar with other items that operate at such a frequency, even most PCs dont operate that fast.

The degree of exposure thats acceptable can be compared in relative terms. For example, I use a cell phone, but perhaps only a couple minutes a day. So, how would sitting in front of my 4.5GHz CPU, with no case around it, for a period of several hours a day, compare?

It really won't because there is little to no radiation. We aren't talking about RF fields.

And microwave, SHF, etc frequencies have been in use for a very long time, before cellphones, at much greater power levels. Yes, exposure to microwaves is bad, but again this is at higher power levels in radiating electromagnetic fields.

Just don't use the computer without the shielding. I don't see the issue?
 
Just don't use the computer without the shielding. I don't see the issue?

My whole question is based on the fact that I WANT to run the computer with no shielding. Application being custom PC cases.
 
This isn't your PERSONAL computer? You intend to market this?

Well, there are a lot of reasons to shield the computer aside from radiation exposure concerns. As I said, interference in both directions being one example. All electronics radiate electrical fields to some degree. Not so much RF, which is an electromagnetic field. There really are too few coils and the interconnecting conductors tend to cancel each other out because of common mode currents. You'll get a bigger dose of RF from the transformers on the power supply than the microprocessor.

A CPU will show up, however, on a radio receiver tuned at that frequency as a VERY LOW dB signal. I have detected harmonics of my computer's microprocessor clock on my ham radio for instance. We call these "birdies".

And for liability reasons, proper shielding is simply good engineering. I had assumed you were asking a general question for personal reasons.
 
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And for liability reasons, proper shielding is simply good engineering. I had assumed you were asking a general question for personal reasons.

Please dont make any assumptions and only take as fact what I state as so. I have not stated this is for a personal setup or that it is something I am going to market, so please dont assume its one or the other.

The information I have gathered here is that there are no relative health effects of any radiation from PC components. Motivation for shielding would be minimizing interference.

There are lots of "marketed" computer cases that are made of acrylic, which provides how much shielding? Are you familiar with the Antec Skeleton?
 
I'm sorry. I'm not trying to make assumptions. I'm basing my comments on what little you have said. It is confusing when you indicate fear of having an open case, then say you want an open case, then mention custom PC cases. Custom often refers to something you build to someone's specification. As in "Joe does custom paintjobs for $40/hr".

My bad.

FYI, EMI shielding does not "necessarily" require a solid enclosure. If all electronics are properly chassis grounded, a steel "mesh" or even a metal frame will provide a certain amount of disruption of electromagnetic radiation.

The hardware you mentioned appears to be made of steel, not acrylic.

Myself, I wouldn't trust it to be as effective as a solid metal enclosure. And there are plenty of reasons, shock hazard, vulnerability to drink spills, etc, why I wouldn't personally want a computer frame like that.

Also, are you certain that all the other "acrylic" computer cases you are thinking of are not molded around a steel mesh? Or do not have a thin metallic lining on the inside?

They may or may no be. I've never really looked closely. But I bet the frame itself is steel.
 
Ah, now I see what is needed. I agree that safety is not the issue, but interference is. If you are serious about marketing a computer case, do us all a favor and make it so that the finished computer can comply with radio regulatory rules. To understand what that means, and assuming you are in the USA, you really should hire these people (or equivalent) to give advice and provide verification testing for you:

**broken link removed**
 
You're a HAM ke5frf?

Have you ever tried snooping the SVGA signal from a video card? The pixel clock and sync pulses etc are all generated at the same ??Mhz rate xtal locked, would it be possible to tune to that frequency and receive someones video card signal?

Yes, and it's common practice in spying circles :D
 
01sporty, at the frequencies in question that machine is technically very well shielded.
 
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