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Why Does a Screen Re-Draw Make Noises?
grungy asks: "On several computers I have owned, I have noticed an audible noise related to large screen re-draws. A hardware guy once hypothesized that the large memory-move operation was creating electronic 'noise' which was then picked up and audibly amplified by my speaker. I unwired my speaker, removed it from the machine and put it in a different room, and the phenomenon still occurred. At this point I assumed it was something going on/emanating from the monitor itself. Now I have a TiBook laptop with an LCD panel. At quiet moments I can still hear it when I drag windows around. I have tried doing big memcpy's & the like, I don't get the same noise. I've been wondering about this for years. Anybody know what gives?"
Maybe it's all the little ``gates'' opening and closing inside the computer as the electrons flow through system. I have created this same noise effect by ping flooding a host in a test lab environment on a 100Mps Full-Duplex switched network---the network card was actually a four port and I may have been pinging all four interfaces from different systems.
LCDs do not have the electro-magnetic radiation that can be picked up by passing DOJ vehicles for license validations.
In late 1997, a secret comittee was formed and ushed in a new era of aural-based tempest radiation sensors. They created a bill that stipulated all LCD monitors needed audio broadcasting capabilities for governmental remote viewing. It was rushed through congress during secret underworld briefings and eventually passed at the Grand New World Order Council, codified in January, 1998.
Today these signals are still somewhat perceptible in the lower frequencies, but they emit a wide spectrum for large data broadcasts. Simple listening devices can pick up many user metrics, and are not limited to merely what's displayed on the screen.
I hope this answers your question.
I have noticed an audible noise related to large screen re-draws.
Do the noises sound like sounds?
Do the sounds sound like words?
Are they talking?
Talking to you?
Telling you to do something?
Something like...
Kill! Kill! Kill?
Kill the nassssty hobbitses?
For the precious, preciousssss, preciousssssss
Ring?
Yessssss. Yesssssss. Kill the hobbitses!
Opinions on the Twiddler2 hand-held keyboard?
or at least get them from the grocery store instead of collecting them out in the forest.
That should solve the problem quick.
*Turns Calendar Page*
Looks like it's Duplicated backplane dereferencing signal.
You see, the operating system has to keep a buffer of the screen in memory, and similar to dereferencing a pointer, the dereferencing of this backplane, or buffer, temporarily distorts the signal on monitors that haven't been serviced lately.
{DUMMY MODE ON}
Luckily, this is something you can quiet fairly easily. Do you have a screwdriver?
You are hearing noises from yout computer?
Ok, this is what you need to do:
Listen to music. LOUD music. For years on end. Eventually, you will get to the point where you will no longer hear the noises coming from your computer. Problem solved!
Ehh? What did you say? Speak up, son!
I haven't lost my mind!
It is backed up on disk...somewhere...
They are all wrong...
It's a little guy in the computer with chalk, drawing the pictures on the screen. Sometimes when the screen "freezes" - it's him taking a break.
After a long spell at the coomputer you can usually hear him gasping for breath.
When he has run out of colours and he only has blue left - that when you get the BSOD.
For problems, seek only the simplest solution, complexity brings with it more problems.
I've got ones that fart, crackle and squeal. Everybody! Degauss on 3..2..1..
It's the same reason electrical transformers hum
Because they don't know the words?
--Dan
...bury you TiBook in the forest and leave it there....does it still make screen redraw noises? ;-)
'we can also hear the so called "silent alarms" used in some banks'
What exactly is it you do for a living?! Do you hear these silent alarms often?
I addition to that, I can hear my fanless router work. It makes little teeny buzzes and clicks whenever there's data pumping through it. Strange.
"Sometimes, I think Trent just needs a cup of hot chocolate and a blankie." -Tori Amos on Nine Inch Nails
What exactly is it you do for a living?! Do you hear these silent alarms often?
He said he's 100% Irish. I think that's explanation enough.
Any more of these probing questions and we'll probably be seeing your name in the papers, and I don't mean the funnies.