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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.
*cough* preshott *cough* Finally AMD doesn't have the "hottest" CPU on the market :D
Then again, give it until next cores are released ...
just my 2 bytes
The 1990's called, they want your facts back. If anything, lately its Intels P4 generating more heat overall. Anandtech has a useful article on the issue http://www.anandtech.com/cpuchipsets/showdoc.aspx? i=2026
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
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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
You mean before the Athlon had any thermal throttling measures whatsoever? That was the whole point of that video - the P3 would cut off, the P4 would throttle, and the Athlon would just plain burn up.
That video was highly influential in getting AMD to make a thermal cutoff a requirement for a motherboard to be AMD certified. The newer Athlon 64s have thermal throttling circuitry similar to the P4's, as I understand it.
Basically, you completely misinterpreted the video in question. The Athlon burned up because there wasn't any auto-throttling to fail; the Intel solutions performed exactly as they were designed to.
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.'"
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...
"Here Lies Philip J. Fry, named for his uncle, to carry on his spirit"
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.
Wait until they integrate peltiers into their drink cans. That would be kind of neat -- self-cooling drinks!
----- Wtcher Dragon, UDIC
I actually posted it with "its" - the moderators changed it!
While you are right that Peltier devices move heat from one side (the cool side) to the other (the hot side), they also generate a HECK of alot of waste heat themselves. So, great for cooling CPUs, but ussually used only in conjunction with other "extreme" coolers such as a watercooler or a bong. This is because, the more you cool the hot side, the colder the cold side will be. Peltiers are unique amoung extreme cooling in that they can actually cool lower (ussually far lower, when used in conjunction with other extreme technologies) than room temperature. Extreme OC'ers have sometimes (often!) destroyed their systems by letting water wapour condense onto the back of the sub-zero CPUs!
They're really quite amazing devices. I saw one when they first came onto the consumer PC market, about 4 years ago. Bloke had hooked it up to a car battery, and poured some drinking water onto it. Muttered something about the battery being flat, and a few seconds later scraped *ice* of the surface of the Peltier. They're also used to cool scientific equipment, such as CCD imaging devices in medium-to-high power telescopes.
DanielI can't speak for AMD, but I'm positive Intel uses Minx pelts.
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As long as someone rids the world of thermal paste, I will be happy. There has never been a more annoying substance that that crap.
The heat dissipated by a heat sink (with a fan or not) is a linear function of the temperature of the surface of the heat sink.
So if I have a CPU which puts out, say, 100W of heat, and I have a particular size of heatsink, the temperature of the heat sink will rise until the dissipation of the sink is 100W (or the chip melts). Say my heatsink dissipates 100W at 100C. (All numbers are made up.) Let it conduct perfectly, too, to simplify the discussion. If I put out more than 100W, the temperature of the heat sink will rise a little.
If my CPU is directly connected to the heat sink, its surface will be at 100C. If I have a Peltier that is configured to be 20 cooler on the cold side, then the CPU surface would be only 80C (assuming the Peltier consumes no power). So if my CPU is designed to run at 80C, the Peltier is fine; alternatively, I could get a bigger heat sink or a CPU fan.
So you could use the Peltier for overclocking, to reduce the needed size of the heatsink, or to remove the need for a fan. A given heatsink will be able to dissipate more heat for a given CPU temperature (since the CPU is cooler than the heatsink).
The problem right now is lack of surface area. My poor little switch is a prime example of this - the heatsink it shipped with had so much glue underneath it and so few fins that it was a nice toasty 70C! Heatpipes are no good also, because you need a large heat difference between the heat source and the outside, so you'll usually end up with about 50C on the cpu and 60C outside. Also, while peltiers are great, as mentioned many times before, they only MOVE heat, so guess what that means? That's right - you better have a heatsink the size of a radiator to dump all that heat out.
What do Slashdot editors do, anyway?
According to an old Slashdot article a British company called Cool Chip Plc has something that uses the "Quantum Mechanical Electron Tunneling" to achive "unbelievable cooling efficiencies".
According to the Press Release 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.
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