How do I avoid electromagnetic interference during a build?

[dave4shmups]

So I've heard about electromagnetic interference (EMI) being an issue around PCs, and I'm wondering how to avoid it.  I'm also curious as to why it's even an issue these days, since I grew up using an Apple IIe at school, and there were signs warning against having magnets near disks and things like that.  However, with people today using magnetic screwdrivers, and PC cases having magnetic dust filters, I really didn't think that having anything magnetic around computers was an issue anymore.

[TheGlenlivet]

3 minutes ago, dave4shmups said:

So I've heard about electromagnetic interference (EMI) being an issue around PCs, and I'm wondering how to avoid it.  I'm also curious as to why it's even an issue these days, since I grew up using an Apple IIe at school, and there were signs warning against having magnets near disks and things like that.  However, with people today using magnetic screwdrivers, and PC cases having magnetic dust filters, I really didn't think that having anything magnetic around computers was an issue anymore.

It's not.  

A POWERFUL magnet near a hard drive could still do some damage, but if components are turned off, they are pretty much magnet proof.

All other EM fields that you would find in a home environment you don't need to worry about.

[TempestCatto]

It's no issue anymore. Not unless you take some really powerful neodymium magnets to a specific component. Magnetic screwdrivers and filters don't have any ill-effect on any pc component, even when touching them.

 

The only time you'd have to worry about EMI is if you were in say, a hospital like environment with MRI machine, X-Ray machines, etc. Or an industrial setting with lots and lots of heavy duty machinery working. Even if your pc is next to your microwave, you'll be fine. Mine is literally FEET from our microwave here at home, and the only thing that happens is my 2.4Ghz wireless headphones disconnect until the microwave is done.

 

You won't have any EMI during your build, nor using your machine. Use those magnetic screwdrivers to your hearts content - especially because they make installing motherboards way easier.

[porina]

In the old days CRTs, floppy disks, and hard disks to a lesser extent might possibly be affected by strong magnets. Even then, technically that's not EMI and it doesn't have the "E" part. Magnets are magnetic!

 

EMI would generally refer to electromagnetic waves at any part of the spectrum, although regulations for EMI and electronic equipment tend to focus around radio wavelengths, covering both the emission of, and immunity to EMI. Electronic products are designed to be resistant to these at normal levels. Generally at worst they'll malfunction. It wont be strong enough to cause lasting damage in normal environments.

 

28 minutes ago, TempestCatto said:

Even if your pc is next to your microwave, you'll be fine. Mine is literally FEET from our microwave here at home, and the only thing that happens is my 2.4Ghz wireless headphones disconnect until the microwave is done.

Interesting observation, but probably nothing to be worried about. I don't know the exact numbers off the top of my head, but take Bluetooth for example, the power of that is of the magnitude of miliwatts. My microwave is 800W (more powerful models are available) so we're in the ball park of a million times difference in power level. The microwave oven will try to prevent any leakage of that power, but even if a tiny fraction does get out, it could be enough to disrupt other devices working in the same band, even if not exactly on the same frequency. Ok, looked it up, class 2 Bluetooth (up to 10m range or about 30ft) is allowed up to 2.5mW, and class 1 (up to 100m range, 300ft) is allowed up to 100mW. So I'm in the rough ball park there. Obviously, longer range devices like mobile phones will be higher power than that.

[TempestCatto]

5 minutes ago, porina said:

Interesting observation, but probably nothing to be worried about. I don't know the exact numbers off the top of my head, but take Bluetooth for example, the power of that is of the magnitude of miliwatts. My microwave is 800W (more powerful models are available) so we're in the ball park of a million times difference in power level. The microwave oven will try to prevent any leakage of that power, but even if a tiny fraction does get out, it could be enough to disrupt other devices working in the same band, even if not exactly on the same frequency. Ok, looked it up, class 2 Bluetooth (up to 10m range or about 30ft) is allowed up to 2.5mW, and class 1 (up to 100m range, 300ft) is allowed up to 100mW. So I'm in the rough ball park there. Obviously, longer range devices like mobile phones will be higher power than that.

I have a 1200 Watt unit, and the number one complaint about it in the reviews is it's "noisy" as in RF/EMI/whatever the fuck. So people's wifi cut out when it's in use. It cooks really well though. Our old one died and we needed a new one asap, so we picked up the highest powered one we could at our local Home Depot.

[dave4shmups]

OK, thanks for all of the replies!