turning off computers

I came across this in a discussion of a recent Intel bug, and thought it might be useful to some people here:

"The last time most computers actually 'turned off' was back when AT [power supply units]
still had a power button that actually switched mains voltage.

When [the] ATX [standard] was introduced, the power button moved to being a low voltage
signal to a [connector] on the motherboard, so it was just a question of
what flavor of soft-off you were dealing with.

At a minimum, the motherboard had to be able to receive power button [signals];
wake on PS/2, USB, LAN, or [clock] obviously required the
applicable peripherals to also remain somewhat on. In systems that
have it, the [remote management] processor also never sleeps, nor does the [network card] it
uses (except possibly under some conditions with battery powered
devices, I think at least some versions go full off if the laptop
isn't charging in order to avoid draining the battery). "

In other words, turn off your computer at the power strip, because its switching power supply will inject dirty power into your wiring if you don't.

yes on one of mine or all three i can see a red light glow inside so ill turn off the back switch

This goes for all other devices by the way. Printers especially!! They make some of the worst fields even when completely off, just because they are plugged in.

Don't unplug your laptop(to work on battery) and leave the power supply plugged in for example. Unplug it at the wall. There are power bars with remote controls that work well for this.
You can get one for the TV, computer etc. Once done, push the off button. Your power will be cleaner.
I think even flashlights with a soft on/off button can emit something.

Power bars with remote controls?  Do you have a link for something like this?

 

Sure,
http://www.belkin.com/us/p/P-F7C01008/
I got it from Home Depot.

They call it the "Conserve Switch"

I've tested it with the AM radio, nothing strange coming out of it. Some power bars have USB now, and they have a lot of noise coming out of them from the switching supplies inside.

This power bar also has some EMI filtering. I can pick up the noise reduction when I plug in my fridge in it. The rest of the home wiring has less noise this way.. almost reduced to no noise from the fridge. Most surge protectors do this also however, so nothing special about this one I think.

sailplane wrote

I think even flashlights with a soft on/off button can emit something.

I've had the same impression, but wasn't able to detect anything with either my ED88T or my RS 12-467. I keep them away from where I sleep. A lot of flashlights with variable brightness have a PWM dimmer, so it's easy to understand why they would be a problem when running at a low setting.