Quote:

"For Use With the Pentium® 4 processor
(423 Pin, Xeon™, Foster, Prestonia, Gallatin)"

No Socket 478 I guess.

Sad indeed, but even if they did have them for Socket 478 (or if these work with Socket 478 with a little ingenuity), they don't seem available through any retail channels. At about 4.5" tall, it probably would fit in most mid-tower or bigger cases. But I wonder about the performance of the unit when it's not vertically oriented (as it would be in the servers for which the design is intended). Not to mention the fact that good performance clearly relies on having serious airflow-- check out the diagrams at the bottom of the page. Note that their airflow graphs start at 150 feet (cubic feet, I presume) per minute.

Still, I wonder if we'll see a design like this made for desktop systems. The fan would have to be mounted sideways-- perhaps blowing up towards a PSU intake? Until then, we'll have to make do with Zalmans for our pseudo-passive P4 Cooling needs.

I think its cubic feet per hour still sad. Just shows what could be done if Intel/AMD thought it was worth it

Okay, I went and googled the term like I should have and here's what I found:
Converting air flow velocity "V" to cubic feet per minute "CFM" is easy!

So, by their formula, an 80mm Panaflo L1A which provides 24 CFM over a surface of Pi*80mm^2 would have a FPM rating of:

Area in Sq Ft. x FPM = CFM
Pi * (80mm / (25.4mm per i x 12 i per ft))^2 x N FPM = 24 CFM
0.216 sq ft x N FPM = 24 CFM
N = 110 (units cancel)

So, extrapolating from the graph for the heatsink linked above, we see that with the heatsink in an "open duct" configuration (which I assume describes an attached or nearby Panaflo better than "closed duct"), you get a thermal resistance of about 0.47C/W, which puts it about dead even with the Zalman 6000Cu. (Based on the thermal resistance of the Zalman in the SPCR heatsink roundup with a Panaflo at 12V.)

Anyway, the point is that the "passive" coolers you see around designed for server systems aren't "passive" in the sense that they require no airflow. It's more that they are designed for server farms that have crazy ductwork that forces air into the systems, without the need for tiny, breakage-prone fans all over the place.

Sorry to put a damper on the party, but if you want to dissipate the heat from a 30W+ CPU, you need airflow (or waterflow). Although anyone who wants to prove me wrong is welcome to try.

Aavid Thermalloy also makes extrusion profiles suited for natural convection. Just select a heatsink with thermal resistance between 0,3 and 0,4 , and it is big enough to cool a processor. However connecting this kind of heatsink to cpu and removing it is difficult. I'm simply using ax-7 and extrusion profile on top of it, but there should be better ways.

How big is your heatsink I can see that I can get a big enough one in my case ?

Whats an ax-7 ?

How much did the heatsink cost?

What c/watt do you think would be appropriate for an AMD chip ?

Try the NCU-1000. Search on google for NCU-1000.

Well, I'm more than happy to eat crow on this one. Those are some MASSIVE heatsinks. Actually, I now remember bluehat's earlier post with pics of his heatsinks.

Anybody know any retailers for either the big Aavid heatsinks or the NCU-1000?

Bluehat-
Do you have your PC enclosed in a case, or do you just leave the parts sitting out? It's hard to tell from your pic-- the motherboard's on a tray (for card stability, I guess), but everything else looks like it's supposed to just sit there.

NCU-1000 can be ordered from Japan (once it is again in stock):
http://www.tsheatronics.co.jp/zen/engli ... 000_e.html
Looks like psu fan is needed. On the other hand, non-undervolted/clocked 2,8ghz p4 produces so much heat that it can't be easily cooled without fans, unless heatsink thermal resistance is low enough.

Aavid heatsinks here:
http://www.aavidthermalloy.com/sales/index.shtml
However extrusion profiles are quite common in ordinary electronics shops, and they also tell thermal resistances and other necessary information.

I don't have any case yet, I only took the mb tray from old tower case. I can't even fit sandbagged hd inside a regular desktop case. Mass storage is so heavy that even I build a case for these components, it is still unmovable.