On-CPU Peltiers From AMD?

Hack Jandy writes "Remember those people who lived on the edge and put peltiers between their CPU and heatsink (or your favorite beverage)? A peltier is a devices that gets cold on one side and warm on the other when an electrical current passes through it. It looks like there is talk that AMD will actually incorporate some of these devices on the CPU according to Xbitlabs. AMD already incorporates some degree of the peltier effect with it's Silicon on Insulator."

Peltiers?

[polecat_redux]

I have had limited experience with Peltiers in the context of CPU overclocking, and I must say, my impression was that they're not all they're cracked up to be. Yeah, with a large enough cooler, you can drop the temp of the CPU significantly, but the effect is dependent on your ability to remove the heat from the other side (which is in excess of that given off by the CPU to begin with). A good water-cooling solution works well enough without the need for the extra drop in temp.

Re:Good news - huge steps towards CPU cooling

[polecat_redux]

Or maybe a jug of liquid nitrogen...

LN2 is fine and good as long as you have a replenishable supply, and asphyxiation doesn't concern you all that much. That being said, it still looks like a lot of fun [tomshardware.com].

Re:Well..

[Anonymous Coward]

stop spamming your referral link asshole

Getting the heat out of the chip

[caseih]

Maybe I'm wrong here, but it doesn't sound like AMD would be using the peltier as a replacement for the fan and heatsink, but rather building in a peltier into the silicon itself to pump the heat out of the CPU core itself faster, so that the heatsink and cooling fan on top can keep the core cooled. As someone mentioned, as we increase the density of the cpu die itself, the thermal density is also decreased and thus the problem becomes getting the heat from the core of the silicon wafer out to the outside of the chip or wafer itself. If we put peltier material into the wafer, we can electronically pump this heat to the surface where traditional cooling devices can disappate it into the air

Re:What about reliability?

[ArbitraryConstant]

It's not a bit more heat. It's a lot more heat.

The only time they're worth it is when you're trying to achieve a temperature below the ambient temperature. Otherwise, it's easier to put a heat spreader on the chip (as AMD and Intel already do) so the contact area with the heat sink is bigger.

These peltiers aren't going to go in any general purpose CPUs as we know them.

Power considerations?

[MetalliQaZ]

I suppose this will be strictly for their desktop processors, since the Peltier effect truly consumes a very large ammount of power. I couldn't see this technology being used in any rational way on a mobile proc, and since the two markets are converging, I question this move from AMD. Anyway, it will be interesting to see in what form this technology is actually realized...

Q = UAdT

[Anonymous Coward]

Q = Heat transfer rate
U = thermal conductivity coefficient of the 2 surfaces
A = area of the surfaces in contact
dT = delta T temperature difference

A peltier allows the dT to be much greater (on both sides) so you can transfer more heat in the same space, or the same amount of heat in a smaller space.

The hot side of the peltier can get VERY hot so air-cooling 130 degree fins with 35 degree air much easier than cooling 45 degree fins with 35 degree air.

Re:Stop confusing it's and its

[Hack Jandy]

I actually posted it with "its" - the moderators changed it!

Editors?

[Max Threshold]

Aren't editors supposed to catch and fix simple grammatical errors in submissions? Isn't that part of what editors have traditionally done?

What do Slashdot editors do, anyway?

Quantum Mechanical Electron Tunneling ?

[Taco Cowboy]

According to an old Slashdot article [slashdot.org] a British company called Cool Chip Plc [coolchips.com] has something that uses the "Quantum Mechanical Electron Tunneling" to achive "unbelievable cooling efficiencies".

According to the Press Release [coolchips.gi] it is claimed that the device is so good that "a panel about two inches square will have the capacity to provide the air conditioning for a living room" !

In comparison, according to Cool Chips's press release, most existing cooling systems use compressors and environment-damaging fluids and are 40-50% efficient. Smaller thermoelectric cooling devices, despite more than $1 billion spent on research, are only 8% efficient. Cool Chips, on the other hand, are projected to operate at 70-80% of the maximum theoretical efficiency (Carnot) for cooling.

I am not affliated with "coolchips" in any way, just in case you wonder.