News Test Processor With New Thermal Transistors Run 13 Times Cooler

[Admin]

Experimental thermal transistors may be a future solution to increasingly hot CPUs, GPUs, and other processors.

Test Processor With New Thermal Transistors Run 13 Times Cooler : Read more

 

[chaz_music]

About 20 years ago, I talked with Nextreme (now Laird) about using their Peltier devices being used internally in processors and LED chips. Since the Pelitier material is semiconductor, someone should have figured out by now how to embed Peltier junctions where they are needed and create a thermal cooling channel on-die. Unless they did and the idea is not out in the wild yet?

 

[Diogene7]

Well really incremental improvements to silicon transistors is close to reaching its limit, and therefore it would be better to significantly invest in next generation computing technologies like spintronics related technologies (MRAM, Intel MESO concept,…) as it seems that could improve power efficiency from 5x to 30x…

I don’t understand that at this stage DARPA and the US government (US CHIPS Act) still don’t yet make it a top priority for the US to regain its leadership…

 

[ekio]

13 times cooler... what does it mean even ?
The processor is 10 degrees instead of 130 without cooling system, it's 5 degrees compared to 65 with a classic cooler, it's 1/13th above room temperature, it's no cooler - room temp + 1(/13* room temp). etc ???
Explain properly what it means!

You guys put some blurry figures often and nothing is making any sense nor explained....

 

[Ravestein NL]

Maybe it's possible to recycle the processor's power by using the heat to electricity way like those ventilators they make for wood stoves! And so lowering the power the CPU uses!

 

[TJ Hooker]

13 times cooler... what does it mean even ?
The processor is 10 degrees instead of 130 without cooling system, it's 5 degrees compared to 65 with a classic cooler, it's 1/13th above room temperature, it's no cooler - room temp + 1(/13* room temp). etc ???
Explain properly what it means!

You guys put some blurry figures often and nothing is making any sense nor explained....

The 13x value is the difference in thermal conductance between the thermal transistors being in an 'on' vs 'off' state. Not the difference compared to conventional cooling methods, as incorrectly stated in this article.

I'm not sure why that's an important metric though. At least in the context of cooling computer chips, simply having high thermal conductivity seems like key property, rather than the ability to change conductivity. The IEEE article also highlights the frequency at which the thermal conductivity can be switched, which I also don't understand the significance of.

 

[chaz_music]

Maybe it's possible to recycle the processor's power by using the heat to electricity way like those ventilators they make for wood stoves! And so lowering the power the CPU uses!

I like that style! Your idea would be novel - except it causes heartburn. You are talking about embedding a thermocouple or other form of Peltier device inline with the CPU heat flow to extract energy. That comes at a cost.

Any energy conversion requires the same idea as a "voltage drop" and "current flowing through it". Heat is the same.

Let's start with thinking about motors. In motors the output mechanical power is P = torque x speed, which requires the duality on the electrical side of "current" (very strongly related to torque in the motor) and "voltage (very strongly related to speed). AC motors can be a little more complex than that, but DC motors are on a first order, exactly like that. Speed correlates to motor voltage, torque relates to motor current.

When a Peltier device is generating electrical power, it is creating an output voltage. And if there is a load, some output current. The thermal part of a Peltier device will have temperature drop across it (think of thermal resistance) as the heat flux goes through it (like electrical current). So heat flux (Q) on the thermal side is related to voltage on the electrical side, and temperature drop on the thermal side (delta T) is related to current on the electrical side.

On the aerospace projects that I've used Peltier devices on, we even used this to modulate the heat flow. Short the electrical side together (no voltage drop) will give you the lowest temperature drop on the thermal side. Opening the electric circuit side gives you the largest temperature drop on the thermal interface part.

But note: present day Peltier junctions are really pretty bad, and are not efficient. For instance, they would not terrible to cool your house, as they exist right now.

But there have been CPU coolers made that you put electrical energy into a Peltier junction to cool the CPU more. Just like a heat pump on your house.

 

[AgentBirdnest]

So, it's made by JayzTwoCents?
What an odd photo choice for this article. A billion photos of CPUs, and y'all went with a JTC screengrab. : P

 

[The Historical Fidelity]

The 13x value is the difference in thermal conductance between the thermal transistors being in an 'on' vs 'off' state. Not the difference compared to conventional cooling methods, as incorrectly stated in this article.

I'm not sure why that's an important metric though. At least in the context of cooling computer chips, simply having high thermal conductivity seems like key property, rather than the ability to change conductivity. The IEEE article also highlights the frequency at which the thermal conductivity can be switched, which I also don't understand the significance of.

I think it represents the technology quite well. By having the thermal transistor in its off state it shows the properties of the physical material used to create it, and the 13x increase in conductivity when it is on proves that the performance is more than the sum of its materials. However, I agree it does nothing to show its effects on a chip’s temperature.

It’ll be interesting to see how manufacturers choose to utilize this tech. Perhaps they will test out a chip without thermal transistors and determine areas in need and re-design with these thermal transistors in key areas. I hope the tech will be used to normalize the thermal output across the chip, IE: no more hot spots on the chip.

 

[bit_user]

The 13x value is the difference in thermal conductance between the thermal transistors being in an 'on' vs 'off' state. Not the difference compared to conventional cooling methods, as incorrectly stated in this article.

I'm not sure why that's an important metric though. At least in the context of cooling computer chips, simply having high thermal conductivity seems like key property, rather than the ability to change conductivity.

For a chip with a hotspot, you'd better be able to remove that heat if you had a dedicated channel to draw heat away from it, rather than a shared channel that's pulling heat from everywhere else, also. The reason being that a dedicated channel should have a higher temperature delta, and Newton's Law of Cooling tells us the rate of thermal transfer is proportional to the temperature delta.

Because a CPU is a dynamic thing, these hotspots surely move around, depending on the code being executed & the data it's processing. If your hotspots move around, then you need a way to dynamically admit/block heat to that channel. That's where I see value in the thermal transistor idea.

The IEEE article also highlights the frequency at which the thermal conductivity can be switched, which I also don't understand the significance of.

If you're going to dynamically reconfigure your thermal channels, then you need to be able to do so about as fast as the hotspots move around.

 

[t3t4]

The design innovation that made this possible was a one-molecule-thin layer of molecules that become thermally conductive when charged with electricity

This quote kinda hurts my brain. A molecule of what exactly? For some reason I'm envisioning 'ion wind' through a 1 molecule air gap.

Otherwise this idea sounds a whole lot like a TEC/Peltier which are anything but power efficient! So it can't be that, can it?

 

[NatalieEGH]

As the author is discussing this, it would have been nice to get a paragraph mentioning competing technologies like on chip liquid cooling and a comparison of efficiencies and expected developmental times/costs with possible appearance in enterprise and then consumer electronics.

This while mentioning their may be an electronic way of improved cooling gives no hard numbers for the current investigations as commented on by "AgentBirdNest and ivan_vy".

The article as presented is very similar to vaporware articles. "We have discovered a solution" rah rah when it actually seems on closer examination to be in the earliest stages of BASIC research with no current idea when DEVELOPMENTAL research will begin.