I want a passively cooled desktop/cpu/gpu by 2016, power supply may have fan.

This website mentions 10 watt idle and 29 watt active for gt 520 which is a good example of a chip being passively cooled, though power supply does suck some heat from it probably:

" Power consumption should also be similar; NVIDIA gives the GT 520 a TDP of

29W, while we?d expect the idle TDP to be around 10W. "

So 25 watts seems to be on the safe side.

Bye, Skybuck.

• and laptops

Hello,

I play to buy a new computer by 2016, currently I am concerned that the computer I want is not for sale/possible.

So far intel and/or amd is not selling passively cooleable CPUs for desktops ?! Could this explain the decrease in PC sales ? People diverting to noiseless tablets ? *

Amazing that no passively cooleable cpus seem to be for sale ?

With passively cooleable cpu I consider:

1. CPU + heatsink with fins smallist, no fan, no other things, except maybe thermal paste interface material between cpu and heatsink.

So two questions:

1. Which desktop cpu by 2016 will be passively cooleable ?

1. How many watts are passively cooleable with a small heatsink/fins, like gt 520 from asus is a good example.

(Also the motherboard must be passively cooled as well as all other components except perhaps power supply, though if a modest power supply is needed might be passively cooled too, but a little bit of airflow seems wise... though would be cool if it wasnt needed at all, than no dust in pc which would be excellent.)

Bye, Skybuck.

As is so often the case, your questions are so poorly defined that there is either no answer to them, or dozens of answers (some being quite silly). For example, you can certainly cool a thousand-watt device with a simple passive heatsink with fins, but you're likely to find the operating temperature and lifetime of the device to be inadequate for home use :-)

There are now, and have been for years, Intel (and compatible) CPUs which gave good performance for their era, and which were passively cooled. Many of these were and are quite suitable for use in desktop systems and notebook computers, assuming proper system design.

A lot of these are sold as "industrial computer" or "embedded computer" devices rather than "desktop", but they run the same code and do the same jobs... the terminology is as much marketing-speak as it is real.

For a simple example: I've got a single-core, hyperthreaded Intel 1.6 GHz Atom N270 at the heart of my home firewall / VoIP server / email server / Web server, on a mini-ITX motherboard mounted in a desktop-computer tower case. It's passively cooled... just a small finned heatsink... no fan on the CPU or on the motherboard chipset or DRAM. The only fan in the box is in the ATX-style power supply... and I could have done without that if I had bought the version of this motherboard which has a simple 12-volt power input jack, and ran the whole system from an external switching "wall wart" power supply.

A lot of the "industrial PC" systems I've seen are not only passively cooled, they are sealed boxes (hermetically sealed or close to it)... intended for operation under harsh conditions (dust, humidity, vibration) they depend entirely on passive cooling. Typically they'll have some sort of mechanical head-spreader between the CPU and the case, so the case and its external fins serve as the cooling system.

If you're fixated on "desktop" CPUs (i.e. those which can be installed into sockets on traditional motherboards in traditional "desktop" cases)... well, the vendors seem to focus more on performance than on passive cooling, and so you may not find anything to your liking. That's even more true for GPUs, for which performance is almost everything... and so they run the chips fast, and this generates a lot of heat. I rather doubt that these traditional-market "desktop" systems will focus on passive CPU cooling any time soon - there's not much incentive for the manufacturers to do so.

You can reduce the heat generated in almost any CPU or GPU by underclocking it and turning the voltage down, but of course this costs you much of the performance.

As to your question about "how many watts" - until you define the actual heatsink, *and* the environment in which it's operating (e.g. case air-flow if any, extra heat spreading, air temperature inside the case, etc.), tell us what sort of temperatures the CPU chip can handle, and how long you want the CPU to survive the heat, there's no way for anybody to give you a solid answer.

As a very rough rule of thumb, though, I would suggest that running more than about 4-5 watts, in the chip the size of a modern CPU, will require either some form of forced air across a heatsink, or some fairly direct thermal connection of the chip to a larger heat spreader. Beyond this point, a modest finned heatsink which depends on air convection and radiation isn't going to keep the chip cool enough for a good long lifetime. The larger the heatsink you are willing to tolerate, the more heat you can dissipate without needing forced airflow.

This all may be irrelevant, though. Apparently, Intel has announced that they plan to discontinue their lines of desktop CPUs which plug into sockets. They're going to be moving their new CPU lines to BGA (ball-grid array) only, and these must be soldered to the motherboard. "Enthusiasts" will no longer be able to buy a motherboard with socket, and populate it with the CPU of their choice... you'll have to buy the motherboard with the CPU already soldered on, and will not be able to change it (BGA removal and rework is possible but it's a terror, from all I've heard).

So, your 2016 Dream PC may be an Impossible Dream.

--
Dave Platt                                    AE6EO 
Friends of Jade Warrior home page:  http://www.radagast.org/jade-warrior 
  I do _not_ wish to receive unsolicited commercial email, and I will 
     boycott any company which has the gall to send me such ads!

Why shouldn't they be able to do this?

After all, look at the chips they're putting in tablets these days. They don't need fans, and they're a lot more powerful than the 386 chips of yesteryear that didn't need fans.

So why can't you buy such a desktop computer right now?

Well, two reasons.

Microsoft doesn't sell Windows 3.1 any more. To run the operating systems it sells now, the CPU's power has to be big and bloated like the operating system it runs. Even laptops these days have fans.

A deskop computer costs more money than a tablet. So if you're going to pay that extra money, you want to get somethng for it. Like the ability to run Windows programs.

John Savard

Actually most notebook PCs have fans, but they are very quiet when running. I've used my Dell ATG in a desert environment (ambient around

46 deg C) and I assure you the fan was running.

The Panasonic Toughbook 30 was fanless. It was full of heat pipes. I'm not sure about the 31 version.

You need a very open case to run an Atom fanless. It can be done in moderate environments, but a small fan works wonders.

With netbooks not selling well, Intel hasn't bothered to put the Atom on their finest geometry process, which would help with TDP.

My old Dell P4 mini tower(circa 2005)runs 24/7. Every year or so I take it to the garage and blow out the dust with compressed air. Lots of dust comes out of the cpu tunnel sink, but not much out of the ps or the rest of the case. Maybe the guy needs to look at his housekeeping/lack of housecleaning. My place is not the cleanest in the world, but we do run the vacuum regularly and change the filters in the HVAC monthly.

I rarely see a blown Intel CPU. However, dead motherboards are epidemic. Lots of reasons, but basically anything that's customer accessible will eventually be broken. On laptops, BGA soldering failure is the most common source of total failure. So, if we take a nearly 100% reliable Intel chip, and couple it with a not so reliable motherboard held together by a not so reliable interconnect scheme, we get a not so reliable combination. That should sell plenty of un-necessary CPU's to fix motherboard issues, which I suspect is the intent.

I have a cheapo hot air SMT workstation, which isn't adequate for reballing. I've had some success reflowing HP Jetdirect cards, but not much else. It's not easy.

By 2016, we'll have connectors installed on our foreheads, with wires going directly to the various brain centers. Never mind all the messy and inefficient middleware and user interfaces. You'll also be wearing your computer, not sitting in front of it. If that's to futuristic, I seriously expect to have an intelligent conversation with a computer in the near future.

Everything you know and own will soon be obsolete.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

Given enough plumbing, it's easy enough to cool your CPU without a fan. It's called a heat pump. In its simplest form, get a water cooling kit for your mythical desktop, run plumbing into a deep hole in the ground, and circulate the water. For the typical 100 watts of dissipation, this is fairly trivial. Just make sure the hole hits the water table as wet earth is far more thermally conductive than dry earth. If that's too much trouble, find a solar water heater and run it as a big radiator to radiate your heat to the atmosphere. While not as efficient as a heat pump, almost any manner of radiator will be sufficient to radiate 100 watts. If that's too much for you, consider building a garden fountain. Just heat the water going to the fountain and atomize the water with a spray nozzle. Recirculate any water that falls back into the fountain bowl. Lots of other ways to dissipate the heat. What's important is to NOT dissipate the heat inside the house, which will make the computah unusable during the summer heat.

Incidentally, Intel makes chips for industrial computers that usually don't have fans. Also, there are heat sinks for Pentium 4 and i-series processors that don't require a fan. However, they're huge and do require some air flow to function: etc...

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

Get an Intel D525MW, and pick the box/power supply to get a fanless one. Use a solid state drive. Very nice package, and insanely small. There are some units that can be as small as a paperback book. I have built a number of these systems for special applications, all totally fanless. The Atom CPUs run QUITE cool even with no fan-forced cooling.

Jon

You could do this if you clocked them slow enough. Not many people are interested in doing that on the desktop platform. If you want something not many other people want, it will be either unavailable or very expensive.

These things exist. They're just less powerful and/or more expensive.

My "home office" is in the living room, so my home desktop needs to be very quiet.

For about 5 years, I've had an AMD Athlon X2 4800+ passively cooled (with a monster heatsink), tho the whole machine still had 2 fans: one for the power supply about which I don't know much, except that when it got noisy I bought a new power supply; and another fan for the system, the typical 120mm fan running at the lowest possible speed.

I retired this machine and replaced it with a mini-itx system hosting an AMD E-350, again passively cooled. This one doesn't have a system fan, tho I haven't bought a pico-PSU yet, so it still has a fan within the power supply.

In the real office, I use a fit-pc2 which is fully fanless, and if you're interested in fanless PC, I recommend you take a look at

Stefan

ops

be

e s c

As a big proponent of silent computing, I've been slowly working towards a completely silent PC (which implies fanless). Here's a few of my notes.

1. Power supplies *can* be fanless; there are several on the market. But the one I ended up using was the SeaSonic X series, which only turns on its fan when necessary. Under normal situations (web browsing, email, MS Word, Excel, even youtube) the fan stays off. Only when I boot up games or photoshop does the fan turn on.
2. Heat management is key. You must have a case design meant to deal well with heat. For example, my PSU is mounted at the bottom of my case, so that the PSU stays as cool as possible, so that its fan runs less often (because no internal components heat up the PSU).
3. Completely fanless cases tend to have huge built in heat sink fins on the outside of the case, so that heat pipes from CPUs/GPUs can be connected directly to the case, to radiate heat. Due to attaching heat pipes to the case, it places some pretty hefty design constraints on your internal components, as they now have to be physical compatible with the case.
4. Hard drives make noise. In fact, in my current system, they make

*more* noise than my fans. Aka, big fans moving slowly generate less noise than a hard drive. So if noise reduction if your objective, it is not necessary to be completely fanless, only to be quieter than your hard drives.

1. Water cooling can be very noisy, because water pumps are noisy (in fact, it's actually rare to find a quiet pump). Thus, a water cooled, fanless computer can still be noisier than a computer with fans.

--
// T.Hsu

So, you want a Macintosh mini? They've been Intel based in recent years.

Google "heat pipe"

-- Paul Hovnanian mailto: snipped-for-privacy@Hovnanian.com

------------------------------------------------------------------ Shoot straight you bastards! Don't make a mess of it.

No particular reason the power supply has to be in the same room. Move it elsewhere.

Or use flash.

And use 0000 AWG cable to reduce voltage drop.

y

Alrighty... you realize that a typical build uses at least 46 wires running from the PSU, right? 32 to the motherboard (a 24 pin and an 8 pin), 6 to each SATA device, and 8 to the graphics card (16 on higher performance cards). So you are talking about running 46 wires of 0000 gauge, with shielding, several feet, from another room, probably drilling a hole through the wall, just to keep the noise of the PSU down? And this seems more reasonable than a fanless PSU, or a PSU which can shut off it's fan?

--
// T.Hsu

I was gonna suggest earplugs that reduce the noise from the fans and the drives and the clicking of the keyboard and the sliding of the mouse and the furnace and the fridge and the cars going by and the kids playing and the wind blowing and the rain dripping and all the other things that must be driving him nutz.

But, then I realized that the voices in his head wouldn't be affected. Bummer.

You could program the microphone and speakers to emit an inverse wave canceling out all sounds, creating a 'cone of silence' around your PC.

Maybe just imagine an inverse wave for those.