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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."
dont put it on the wrong way.
The problem with peltier coolers is that if it breaks down, the once cooling surface becomes an insulator. Plus, if the hot side gets too hot, the cooling process breaks down, so anyone using this would have to use a cooler that can draw the heat away as fast as the CPU-side peltier can kick it out, which would probably be another, larger peltier.
I'd rather stick to external cooling systems that I can monitor and replace if necessary.
If I have been able to see further than others, it is because I bought a pair of binoculars.
Actually, the funny thing is, this hasn't been true for years. Intel CPUS put out quite a lot more wattage (~90w) compared to AMD's top end silicon, around 70 watts. But it made for a mildly funny joke back when the t-bird was spanking the socket 423 chips.
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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.
Just imagine the amount of power required for something like that. Each core of a dual core 65nm CPU will need at least 70 watts of power, giving 140 watts total. In order for a peltier to be useful, the wattage has to be greater than that of the CPUs. So with only the CPU and Pelt, that is a minimum of 300 watts, with something between 400 and 500 being more likely. That is an absurd amount of power and heat.
eclecti.cc
I don't know where you get this information, but the new AMDs are somewhat cooler running that the top end Pentium 4s.
As for heat coming from the other side, that's one of the issues that an on-chip Peltier would alleviate, but presenting a cooler surface to the CPU on the side with the heatsink.
hot on one side, cold on the other. sounds like my bed.
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.
As mentioned already, Peltier junctions act as heat pumps. In other words, you put work in to extract heat from the processor, this extra work turning into (you guessed it) even more heat.
While it might contribute to the cooling of the processor, you'll need an even bigger heat-sink and fan stuck on top to dissipate all the extra heat...
(Rant: why can't all processors be like the one in my iBook, designed for power efficiency as well as performance?)
Tedious Bloggy Stuff - hooray?
is not just the total amount of heat they put out, but the fact that they put out that much heat over an area of about one square centimeter (on the 90nm process at least). As the physical piece of silicon shrinks, the thermal density increases. More transistors switching on and off in a smaller area, and the drop in Vcc isnt enough to counteract the increase in density (we were at 1.8v or so with the 180nm process, and now at 90nm, we're at 1.4v or so - some chips dynamically change voltage and multiplier based on demand). I'm not sure this will do a whole lot of good if you just try to disapate the heat from the processor and the heat introducted by the peltier effect over the same square centimeter. You'd need to disapate the heat over a much larger area, say 10 sq cm. They you can stay in the realm of air-cooling instead of watercooling.
The Doormat
If you're not outraged, then you're not paying attention.
"A peltier is a devices that gets cold on one side and warm on the other..."
come up with your own shit. my g/f patented this 'technology' years ago
This sig contains repetition and redundancy.
AMD is patenting this as a way of *getting around* of SOI disadvantages. SOI means silicon on insulator , which is in this case SiO2, which is also excellent thermal (not only electrical) insulator. AMD says that SiO2 conducts heat at least hundred times less than silicon.
What they are saying is that transistors on SOI might behave better, but they are certainly running hotter than their classic countepairs, since layer of SiO2 stands between them and the cooling system.
So AMD is proposing several schemes of embedding TEC device into the insulating layer in the silicon. This layer would:
1. Decrease overall thermal resisstance of the cooling path
2. When powered on, offer bigger thermal diferential, since it could cool embedded side of the TEC significantly below the cooler temperature.
It is unclear if they intend to use this on the whole chip, or just the especially hot areas...
Another flamebait. Processors are getting hotter and hotter. Intel used to generally do better in power consumption than AMD. But that period has ended years ago when Willamette core P4 was out. Have you compared the heatsink size of Prescott core P4 and that of AMD64?
I'd be more worried about the heat coming from the other side. My case is hot enough as is, no need to add to it
RTFA. Which "other side" are you talking about?
According to the wikipedia article, peltier effect is "the creation of heat difference from an eletric voltage." Namely, a peltier moves heat from one point to the other with the help of a electric field.
In this case, the peltier moves heat away from one side, the processor, to the other side, the heat sink, and the later then extracts the heat away. It helps conducting heat when the temperature difference between the CPU surface and the heatsink is higher. Although as a semiconductor itself, the peltier also generate heat. That is far less than the heat it takes away from the core and that heat is in effect taken away as well. So I don't know what you mean by "adding heat to it".
People who dislike China tend to mention Tiananmen Square a lot, but they always forget the Tank Man is also a Chinese.
I remember that SGI once used peltiers and they had to recall them because of failures due to corrosion due to condendsation because the device temperatures fell below the dew point.
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
The key thing with peltiers is that they just *move* heat.
Which is exactly what your domestic refrigerator does, merely moves heat from the inside via the evaporator to the outside to the condenser. In fact heat cannot be destroyed at all (think conversation of energy), merely moved elsewhere.
For all intensive porpoises your a bunch of rediculous loosers
Peltier is the guy who discovered the effect. A peltier junction (sometimes called a peltier cooler, which is a stupid name because it's also a heater) is the solid-state heat pump. A peltier junction is not called a peltier.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
He has spent more than twenty-seven years in prison for a crime he did not commit.
He colluded with alternating N- and P-type semiconductors to rob systems of thermal energy that wasn't his to begin with!
Now he's cooling his heels in prison.