Here
Im not sure weather to believe the figures there. At thos temps would the PCBs/Chips crumble away?
Here
Im not sure weather to believe the figures there. At thos temps would the PCBs/Chips crumble away?
Id belive the temps, no reson not to belive it really.
low temps wont make things crumble (unless there hit with something - they will get more brittle, or unless there structure gets so weak it cant support its own weight...)
SilentDeath is right.
Silicon chips are very brittle (compared with metals) however, you would still have to put quite a (tensile or compressive) load on the material before any fracture would occur, even at those temps.
Pcb's being (mainly) plastic are considerably more ductile (flexible) and unless stressed hard wouldn't have a problem. Most of the solders and resistors etc found on motherboards these days are of the same quality as electronics that we use to built satellites, which see a greater temperature difference in operation. We typically thermally cycle these at -55°C to +125°C at 1° per minute as a test.
The bloke is also using digital multimeters to read temperature so it would be unlikely he is faking it.
At that temperature the stuff wont last, he'll get .. ahh crap forgot the term.. where atoms move in thin wires because of large voltages: anyway, itll screw the silicon. Its worse if he warms it too quickly, if he keeps it all cool constantly itll last longer. Metals become more brittle but move towards better conductivity at lower temperatures.
I dont like sig pics so i turn off sigsWhich doesnt help when i dont know what ive written here! DOH!
electomigration? this happens when the votlage or heat is too HIGH and the connductors get stressed, eventually one of to things will happen. the conductors will either branch out to the next nearest conductor, causing a short, possibly killing a chip (this might acctually not kill it, or possibly even improve the chip - this is possibly what burning in does). The other thing that can happen is the conductor will snap - the opposite. This breaks the circuit, and will possibly kill the chip as I said above.
Low temps are good for the chips. current cpu's are (I forget the term used) made so that when one unit of the cpu starts something, all the others have to wait, this is whats reffered to as clock speed. This may not be eactly right, as Ive forgoten... but there are other types of processors that run non-syncroniously and therefore do not have to wait, and do not have a set clockspeed, and just do stuff as fast as the sillicon/other semiconductor will let it. Temperature WILL affect the performance of these chips directly. So by lowering the voltage, the chip will be able to run faster without becoming unstable.
The reson temp affects it is becuase it lowers internal resistance, giving the same affect as more voltage, exept it doesnt stress the conductors (as they are deisgned for that voltage). Remember as voltage increases, so does current, and current is what breaks stuff..
Sorry if you already knew this, and im more sorry if I am wrong, but this is as I remember it.. so please correct me
Anyway to get that temp, he has some expensive equipment, a cpu isnt going to bother him if it dies, he will just buy another...
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