Appletops may get juice pump
Liquids predict toasty future
The latest Apple patent to surface points out that the upcoming mobile round of Intel's Nehalem chips may require more cooling mojo than the current Penryn line.
On November 27, the United States Patent and Trademark Office published patent application number 20080291629, originally filed by Apple on May 22 of last year and entitled "Liquid-cooled portable computer."
The application's abstract describes a "computer system" that "includes a power source that is coupled to a heat pipe, where the power source includes an integrated circuit" and in which a "pump...coupled to the heat pipe is configured to circulate the liquid coolant through the heat pipe."
The filing goes on to describe three possible types of pumps: a traditional mechanical pump, an electrostatic pump, and a mechanical variant that uses a vibrating membrane to circulate the liquid coolant. The coolant would transfer heat from the processor and associated circuitry "to a heat exchanger coupled to the heat pipe...configured to transfer heat from the heat pipe to an environment external to the computer system." Hopefully, that external environment won't be your lap.
Leaving aside the leakage and subsequent system-destruction problems that Apple encountered when it first used a liquid-cooling scheme on select Power Mac G5s earlier this century, the obvious question is why Apple would want to move away from reliable if less-efficient air cooling to the more problematic world of liquid.
Apple's filing answers part of that question when it notes that "Portable devices, such as laptop computers (notebook PCs), cellular telephones, and personal digital assistants have additional design constraints which make it even harder to manage thermal load...Furthermore, battery life constraints in such devices may limit the available power for active cooling mechanisms, such as fans."
In other words, the "portable computer" of the filing's title need not merely be a laptop, but any sort of mobile device, be it a pocket-able platform such as the iPhone or a mobile internet device (MID) such as a tablet or pint-sized netbook. Although the filing's schematics clearly refer to a laptop, Apple is apparently laying the groundwork for future cooling needs.
The next MacBook Pro, pre-Jonathan Ive
The most immediate of those needs will be in the four-core mobile-processing future, scheduled to begin late next year when Intel releases its Clarksfield class of 45nm Nehalem-architecture Core i7 processors. Although official specs for these four-core mobile chips have yet to be released, the word on the street is that they will have a thermal design power (TDP, an industry-accepted measurement of a chip's power consumption) rating of between 45 and 55 watts, a power hunger that will cause them to be quite toasty, indeed.
Compare that 45/55W TDP with the ratings of the Penryn-class chips in the current MacBook Pros. The entry-level model's 2.4GHz Core 2 Duo has a TDP of 25W, and the upper-class 2.53GHz and 2.8GHz versions rate 35W each.
Although a comparatively hefty 45/55W TDP may seem to be a violation of Intel's oft-stated goal of lower-power chips, remember that not only will Clarksfield have double the number of cores in the current Core 2 Duos, but also that it will have its memory controller on-chip, not in a separate chunk of silicon. That raises its power appetite — which may be one reason why even the dual-core mobile Core i7, Auburndale, is reported to be scheduled for a TDP of 35/45W.
Although attempting to predict Apple's product moves is often a fool's errand, we suggest that liquid cooling may first be seen in a quad-core MacBook Pro. We can only hope that the company has learned from the Power Mac G5's unwelcome secretions. ®
This isn't really related to water OR liquid cooling, the patent title is rather misleading. R134a is used in car air conditioners... At regular pressures it's actually a gas, the oddest thing about this whole patent is Apple's insistence on refering to this as liquid cooling. In an R134a setup (for cars) the evaporator has a low-pressure cold gas, this is in the dashboard on a car or would be on the heat plate of a computer. This gas is is heated by the air or CPU (cooling off the air or CPU as a result)... This now-hot low pressure gas is run through the compressor, which compresses this into a hot high-pressure gas. This is run through the condensor (on a car this is the "extra radiator" you may notice on air conditioned models), where it's cooled by air rushing past.. By the time it's all cooled off it's a high-pressure liquid. The high-pressure liquid runs through an expansion valve or orifice tube, at which point it's a cold low-pressure gas (for the same reason that compressed air from a can is cold...) It's now ready to go back into the evaporator.
Two problems with this:
1) Where would you place the condensor? The heat doesn't just go away, this is just a fancy heat-transfer system.
2) Environmental. Apparently the EU has banned new car designs using R134a as of 2011, because its' a greenhouse gas. A computer is not a car, but how green will Apple look putting "banned" refrigerants into brand-new products?
...that comments on El Reg are becoming more and more like comments on Slash Dot.
And that is in no way a good thing.
Re:Re: Ben Heck's 360 Laptop
Yup, here it is, I think:
Can one of you Oh! so enlightened! people tell me how this application points out flaws in the US patent system? Try to put aside your childish vendettas and get a grip for a second; you can file an application for shoelaces if you want. Filing an application does not grant a patent.
But you experts would know that already, wouldn't you? Sheesh, trolls and morons...
@ A. C. re Ben Heck's 360 Laptop...
I believe he's made Mk III just recently. I'm glad that there is someone out threre who is as good at putting things together as he is at taking them apart!
Is there any truth in the news of Apple applying for patents thery never intend to us for the purpose of disguising their future product road-maps?
Coat Icon- man retrieving water-cooled calculator from the pocket.