look for the news DUDE, for example the 140 watt rated phenoms tends to destroy motherboards.
Even asus had to release ones that can handle such power.
Usualy the regulators can't take the load. So makeing sure they have sufficient cooling is important if You wanna get performance for long periods.
allso even brushless dc motors make noise in power lines.
"Brushless motors will not induce any noise in to a line or generate EMI in to the environment." --> thats not true. compared to ones that use brushes its much much better. but still they do make noise.
and.. about the "tin can" --> noise can not just get into there from outside.
You got plenty of stuff inside the case.
About antennas..
http://en.wikipedia.org/wiki/Random_wire_antenna
look there if you do not belive me.
And tell me,
λ = 3×108^8 m/s divided by freqvency in hertz -->
say.. for a 3ghz cpu a 10 cm long cable is enough to catch it.
how true is it? well verry true.
A normal pc psu has 230 ac (or 110 ac..) line filtered with a simple ferrite bead too.
http://aphnetworks.com/report/pc_power_cooling_silencer_610w/010.JPG
like that one.
http://aphnetworks.com/report/pc_power_cooling_silencer_610w/011.JPG
the ferrite bead is visible.
" Computers are classified as unintentional radiators under Part 15 of FCC regulations. Part 15 limits the amount of interference that will be caused by a computer system, but the regulations protect a neighboring home from having television interference when you operate your computer, for example. They are not usually sufficient to ensure that your computer will not interfere with sensitive reception in the same room."
so.. You got long enough cables in there, a LOT of them to get this signal. And Your grounded pc case will not shield any cables inside the case, since most noise comes from within the case.
a computer has many many high freqvency parts in it, one by one they do not couse any problems. But there are situations when they amplify each others waves.
like.. 800 mhz wave and 2,4 ghz wave will interfer with each other,
every 3rd 800 mhz pulse will add to the 2,4ghz pulse. just 2 of the many.
there is allso pci clocks, and a lot other high freqvency stuff in that case, and at some freqvency they will produce a good amount of noise.
for example look around the back of any motheboard, where the cpu socket is.
http://www.meojbiz.com/home/appstorage/product/0000000488/SMD Chip Tantalum Capacitor1.jpg
You will find a shitload of these, they are the small fitercaps.
If You would remove them, cpu could not operate well. It would often freez.
those who are a bit skilled in electronics will notcie that many of these are missing from most motherboards. Solder in the missing components, and You will be able to do better overclocking.
http://67.90.82.13/forums/showthread.php?t=158732
like this dude.
But he replaced the big filtercaps, not the smd ones at the back of the board.
soo yess, if You wanna get a stable system, go for it, and make things shielded, and make sure to reduce noise in lines.
Mostly those little changes in vcore, and other power rails You see while only looking at bios voltage monitors are comming from things like that.
Thats why they repeat periodicly.
question, why won't "overclockers" use it?
they do, but not the "I set xy fsb and cpu multiplier" types.
But those who do have skills to do things right.
allso EMI pollution is probably getting higer in any home nowdays, thats why bios includes the spread spectrum options, to avoid repeating/oscillating collisions with other signals. Most people don't need them, and overclocking wise its BAD to have it on.
but surely adding filters and caps helps any motherboard, many of them are not soldered in regular products, becouse for "avarage joe" it will do o.k. without them.
allso a quick test for Yours "pc case as shield" theory, grab a usb wi-fi product, and place it INSIDE Your case, and see if you can get a reading.
Yes, You will be able. Pc case will not act as a true shielding.
will filter some, but not too much.
Allso notice how a switching power supply works.
And You will notice the 25 khz STRONG signal.
that drives the powersupplys trnasformers primer part.
So much for that.
http://www.serialata.org/esata.asp
esata for example has extra shielding. but even if You do not put your mobo in a case, the unshielded internal sata cable will still work.
thats becouse its filtered, and there are many error corection mechanism.
but it reduces transfer speed.
so anyways, any cable WILL benefit from shielding. Thats the lession.
For serious overclockers its a musthave.
if You change the "big caps" close to the cpu socket with quality products Vcore will not drop under load that much. --> better, way better results.
for EMI inside a computer case, look at this thing-
http://www.everythingusb.com/images/list/siigusb2pcicard.jpg
the port that faces the inside the case was supposed to be used for bluetooth/wi-fi usb sticks, now hows about that?
from the wavelenght calculation You can easyli figure out you got plenty of antennas in there to pick up this trash.
You can do a simple test, even the bios voltage lvl indicators will show a noticable difference if you got a wi-fi product nearby switched on, and specialy if its close to Your computer.
For "best results" get a cpu that runs 2,4 ghz, and get a wifi product that allso uses 2,4 ghz. You will notice the change in the vcore.
if you run stability tests the effect will be realy noticeable.
for a good tuning platform the first musthave is a quality power supply, everyone knows. Now I showd You why. besides power, You need clean power lines. And realy quality PSU has good fitering. Allowing better overclock results.
I hope you are happy now.