-150C Supercooler build....

Quote:

---

Originally posted by zabomb4163

please stop making up information. the critical temperature for Aluminum is 1.19K.
http://www.faqs.org/docs/electric/Ref/REF_3.html [/B]

---

:eek: :eek: :eek:

I was thinking Copper and Silver and wrote copper and aluminium. My mistake, it was a long post and i must have missed that detail.

Quote:

---

I wasn't asking about eletrical charestics but the ability for it to conduct heat and strength of materials.

---

Heat is conducted by electrons or by phonon vibration. Metals don't have the former to any real degree, so for all purposes eletrical and thermal conductivity are two sides of the same effect (delocalized conduction band).

Originally posted by zabomb4163
no offence chilly, but if you read what i posted above you would see that thermal conductivity decreases with temperature. Aluminum will only conduct heat worse the colder you get it.

Not true past -60C aluminum and other metals increase in thermal conductivity, there appears to be a nonlinear blip as themerature drops but as the temps get lower thermal conductivity increases exponentially. So what does this mean if we can get the internals in a chip below -100C and keep it there would we see a nonlinear gain in voltage handeling capability and a substantial drop in temperature with less heat removal and faster load to response times///.

have you been working on the system lately chilly? if so what stage are you working on?

Letting my finger grow back currently.... Almost a candidate for the darwin awards. I was working on a hood system on a roof for a friend and I was adjusting the belt... (Power locked out) I turned the pulley and the sheetmatal gave way and I reacted and tried to catch it... well ten stitches broken bone under thnail the had to stitch through the nail to get it to hold together.... Damn hurts to type.... just took a pill pain be on its way out....

Artists must take care of their hands!

Quote:

---

Originally posted by chilly1
Letting my finger grow back currently.... Almost a candidate for the darwin awards. I was working on a hood system on a roof for a friend and I was adjusting the belt... (Power locked out) I turned the pulley and the sheetmatal gave way and I reacted and tried to catch it... well ten stitches broken bone under thnail the had to stitch through the nail to get it to hold together.... Damn hurts to type.... just took a pill pain be on its way out....

---

Wow that sucks. Hope you feel better and get back in cooling. (I'm going to need advice once i start my system!)

Quote:

---

Originally posted by chilly1
Fuggers old sig had th einsides of the blocks in it... I have a cascade with both. We ar going for all the GHZ we can get so we are also going for as low as possiable with a phase change to -200C....???

---

after i read this i think its about time for you to start stating temps in kelvin :p

When I finish the -150C rig the most xtreme thing I will do next is work on the cryopump (14K) that will supposedly do 70W at 40K and research heat pipe technology operating at these temperatures.... Maybe a while though Istill have projects in teh works...

how far did you get on the -150C before you hurt your finger.

PArts are here layout is dome condenser is on the ground and the third compressor is setting on the floor...

It's nice to see how many people have interests in the scientific things about subzero cooling and electronics.

There are a lot of contradictions about all of this.

a few of them:

The transistor effect has some sort of ideal temperature for electron flow. this point is above ambient.

The shifting effect (don't know how to call it --> the process to change the gate state) tends to go slower if you exceed a certain temperature. (if I remeber corectly)

Semiconductance works with polution of materials. Carbon(oxide) is often used for these purposes. Carbon's resistance tends to decrease, the colder it gets (like most of the materials do).

So there are many factors wich improve under these extreme circumstances, but there are also many factors wich should have a negative effect.

So I thinks it's still very hard to make conclusions, and a lot of scientific tests have to be done to research this phenomenon.

Quote:

---

Originally posted by ns_ripper


Semiconductance works with polution of materials. Carbon(oxide) is often used for these purposes. Carbon's resistance tends to decrease, the colder it gets (like most of the materials do).

---

:confused: carbon has a negative temperature coefficent. as temperature decreases resistance increases. other substances with this quality are silicon and germanium.

and they say european schools are ahead of american schools :p:

http://researchweb.watson.ibm.com/jo...462/nowak5.gif

http://researchweb.watson.ibm.com/jo...462/nowak.html


One possible way to avoid the subthreshold-power vs. active-power box may be provided by lower junction temperature. Since IOFF decreases exponentially with –1/T, the threshold voltage can be lowered in proportion to T while maintaining constant IOFF, allowing further VDD reduction; temperature cuts the Gordian knot among performance, passive power, and active power. Reduced operating temperature further benefits CMOS performance as a result of increased electron and hole mobilities in MOSFETs, and decreased interconnect resistances. The improvement of performance vs. temperature will depend to some degree on details of the CMOS technology and the product design, since the MOSFET performance can improve as much as T–1 to T–0.5 depending on process and operating electric field details, while interconnect (resistive) performance may be improved by as much as T–1.5. In Figure 5, the frequency of the circuit, for a fixed power-supply voltage, will improve as T–, with cases shown for = 0.5, 0.63, and 0.75 to allow for some variability with application. Cooling to 100 K (–172°C) gains two generations of performance (taking = 0.63) and thus looks quite attractive at first glance.

Quote:

---

Cooling to 100 K (–172°C) gains two generations of performance (taking = 0.63)

---

/\ VERY interesting read about processor design and the effect of temperature on processors.

yep! were shooting for those temperatures, stock volts and a 100% gain in switching speed, Increase voltage????? If we can get the required cooling at Vdd +20% what will this do to the effective switching speed, As you may already know increasing the voltage overcomes a limitation of the cmos's switch rise time an decay rate and by cooling we also reduce the decay rate and the rise time., Basically decreasing the temperature has the same end result as a rise in voltage on overall system performance.

Quote:

---

Originally posted by zabomb4163
:confused: carbon has a negative temperature coefficent. as temperature decreases resistance increases. other substances with this quality are silicon and germanium.

and they say european schools are ahead of american schools :p:

---

it's been a while, I leared about this stuff, so I could've been wrong. :D
Apparently I am. :sofa:

So, the theoretical temp where CMOS chips switching time is cut in half is somewhere around -172C, at stock voltage.

so build a system that would cool to -86C with the voltage doubled! and achieve the same effect :wierd:

All this math! Arg, my head :brick:

so chilly, have u considered about try to remove the packaging on the die of a proc, so that the coldness of the evap is touching the actual top layer of the proc, instead of touching the packaging,
although i suppose you would have to find a metal for the evap thats not electricallly conductive.
have you thought about sanding away at the packaging so thats its sides all meet at right angles and then making a perfect indentation of that in the evap,,, or ... taking a mold of the die, and then pouring ur own evap from a mold with a perfect indentation so that it covers all sides of the die except the botton.

i still think my evap chamber with the die exposed directly to the evaporating refrigerant, would work as long as u had a controller perfectly adjusting the amount of refrigeran t flowing and the strength of the suction pulling, for each specific heatload, that the cpu is putting out

I have lapped a proscott worked a little better, iIT's all about boundry layers and surface wetting for heat conductivity. My new evap has only the transferr metal between the refrigerant and the head the baker blocks have an additional boundry layer between the refrigerant and the heads surface. (Bakerblock... refrigerant/metal/solder/metal/hscompound/heatspreader/hscompound/chip=7) My new block... refrigerant/metal/hscompound/heatspreader/hscompound/chip=5.

So if you remove the heat spreader=3 you remove an additional 2 boundry layers and will achieve better internal temps..

So yes it may get you better temps but with the new intel chips comes with a huge risk, the HS Comes off hard and teh chip is realiatively fragile so there is that risk...

Surface wetting is the HS compounds ability to wet the surface. you seen how water beads up? well if you add a surfacant to the water it seems to coat it.. this is what a hs compound need to do... On ultra low applications paladium is commonly used instead of a grease maybe we need to also test these hs greases on ultra low temp apps... good idea blinky,,, maybe we should look into the temperature charestics of the thermal compound intel puts under the heat spreader...

dam intel, btw i just found out theres an intel developmental reasearch place in downtown berkeley, in a building i pass every day going to and from school. im gonna give em a call and see if i can get a tour, and maybe some engineering sample chips. any suggestion on getting these.

Don't know but givem hell.... see what they do there and post you tour take a camera if they let you would be interesting....

i think they do research on wearable computers, but im sure they have some 3.4EE ES's waiting around to be given away to random high school students who walk in :)

heres the stuff they work on
http://intel-research.net/berkeley/research_areas.asp

Get a few hundred samples without the chipkiller already glued on. From now on, i call the heatspreader a coffin.

Quote:

---

Originally posted by blinky
i think they do research on wearable computers, but im sure they have some 3.4EE ES's waiting around to be given away to random high school students who walk in :)

---

I have a wearable computer its a panasonic wearable tablet wirless set up ... win2k p3 500 with 256meg ram... I don't like the current displays as the brightness is only suitable for night use... same as most laptops...