Why arent external fanless PSU's more popular?

[RabidRodents]

Why arent external fanless PSU's more popular?

It seems the insurmountable objective of all Fanless PSU's is the ~500W heat mark. Not only is that a lot of heat, but the case itself is probably air deprived .

By removing the PSU from the case heat equation, you can run your components fanless and they wont build up heat. The PSU is free to take up as much space as it needs for heatsinks, and has enough free air around it to carry heat away. It also has enough wattage to power a decent CPU/GPU. The only drawback would be clutter/space, but I value the silence better .

So why havent they been made? More than 5 companies make fanless PSU's, but only one SUPER SKETCHY company called "XG" (the magnum 600 google it) currently produces them as far as I can see.


...


FUND IT, or tell me why I'm stupid.

[frenchie]

Maybe because they're EXTERNAL...

So when you get a case, you'd also need some place to put the PSU (place with plenty of unrestricted airflow). And they'd have to make the PSU "nice" to look at. And it's doesn't make it very easy to move the case around if you have to drag along the PSU...

Dunno... Just throwing ideas around...

[sNNooPY]

Well, as much as it seems like a good idea, it just isn't practical.

[merlyn]

hardly anybody needs 500W anyway

[croddie]

More than 5 companies make fanless PSU's, but only one SUPER SKETCHY company called "XG" (the magnum 600 google it) currently produces them as far as I can see.

The picopsu is a popular one, combined with a power brick.

[RabidRodents]

Was looking at an Intel i7 // Nvidia 260 // 4x total drives

Was estimating about 500W..

I did look at the pico, and that would probably be enough for just the mobo, but how would I implement all the power bricks for the gpu/hdd's?

Making a silent computer isnt practical in the first place , So.. willing to make cosmetic/space sacrifices.

[FartingBob]

You will have a major problem cooling that system to the point where a good PSU is the most significant noise source.

[Aris]

I can remember around 15 years or so ago, personal computers actually did use external passive power bricks, and it was one of the biggest complaints of users. They hated the external power adapter, and couldnt understand why they couldnt just build it into the case. So thats what they did.

You have to remember, "most" users dont understand thermal dynamics inside a computer or how stuff in there works or why. They dont understand the positive aspects of an external power brick over an internal power supply, and honestly they dont even want to know. They just want it to work, like their microwave oven, and their vacuum cleaner. All they see is a big black bulky box that sits on their desk or on the floor and they dont like it and want it gone. They dont care what consequences that will require.

Was looking at an Intel i7 // Nvidia 260 // 4x total drives

Was estimating about 500W..

That rig is closer to 300w than 500w. Core i7 TDP is around 130w at load, Nvidia 260 is also around 130 at load, HDD's are around 10w each at load. and honestly, every intel processor i've seen lately uses less power at load than what intel states as their TDP.

[m^2]

I can remember around 15 years or so ago, personal computers actually did use external passive power bricks, and it was one of the biggest complaints of users. They hated the external power adapter, and couldnt understand why they couldnt just build it into the case. So thats what they did.

You have to remember, "most" users dont understand thermal dynamics inside a computer or how stuff in there works or why. They dont understand the positive aspects of an external power brick over an internal power supply, and honestly they dont even want to know. They just want it to work, like their microwave oven, and their vacuum cleaner. All they see is a big black bulky box that sits on their desk or on the floor and they dont like it and want it gone. They dont care what consequences that will require.

Was looking at an Intel i7 // Nvidia 260 // 4x total drives

Was estimating about 500W..

That rig is closer to 300w than 500w. Core i7 TDP is around 130w at load, Nvidia 260 is also around 130 at load, HDD's are around 10w each at load. and honestly, every intel processor i've seen lately uses less power at load than what intel states as their TDP.

And some users understand it quite well and still think that having another quite big and ugly box is not worth it.

[Ksanderash]

Usual PSU fan simply blows out warm air from the case through himself -- it kills two birds with one stone. So you don't need to screw in an additional 120mm one on the back side of the case

If the goal is completely silent PC, well, what the heck Intel i7, Nvidia 260, and other hundred watts' heaters had appeared? The SPCR conseption doesn't meen we must take some top hardware and omg! it is heating up terrifically, let's do some cooling!

[RabidRodents]

Haha, thanks for advice. I'll take a look at the 400w Passive PSU's. I was planning on cooling the rest with a Zalman Reserator 1 V2, so I just had the power supply to get over.

And of course, for typical users an external isnt that great, but was just considering silent enthusiests. I could understand the visual blight it would impose though.

[ntavlas]

Such a high wattage system will require a few fans anyway, so you might as well have one on your psu as well. There are many cases with bottom mounted psu`s so if you want you can take it out of the cooling equation.

[Aris]

Such a high wattage system will require a few fans anyway, so you might as well have one on your psu as well. There are many cases with bottom mounted psu`s so if you want you can take it out of the cooling equation.

It doesnt have to be bottom mounted to be thermally separated. The NSK3480 has a thermally separated zone for its PSU, which is mounted at the top.

And of course, for typical users an external isnt that great, but was just considering silent enthusiests. I could understand the visual blight it would impose though.

You can get a passive external AC/DC 300w brick. But you'll have to do some modifications to get it to work. Theres a thread on the forum with pictures on how to do it somewhere. I have one, though i'm currently not using it. I do foresee a day when i will use it.

[inti]

I can think of a few reasons:
(1) Clutter
(2) Cabling
(3) Case cost - the external PSU would need a proper case

Clutter - you'd need a large separate box, which needs to be put somewhere

Cabling - ideal solution would be some type of modular connector at the back where the PSU power lead normally goes (with modular cables inside the case) but then between the PSU and that rear connector you'd need the standard tangle of 30 or more power cables - for low voltage DC at high power, multiple cables are needed just to keep the cable resistance low (power loss in cables is I^2 * R, where I is current and R is cable resistance)

Case cost - for electrical safety and EMI reasons, an external PSU would be an electrical component requiring a proper insulated case of its own - that would probably reduce its airflow, as well as adding to cost.

Indeed, the XG Magnum 600W which somebody mentioned has all three of these issues.

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I think a more interesting question is, why don't external PSUs have the option of a large external heat sink? I mean a big chunk of metal which you could bolt onto the back, after installing the PSU in your case - that would help cool the PSU, take a lot of heat out of the case, and also it might be in the case-fan outflow area so it would benefit from a bit of "free" air cooling.

A few older external PSUs have rather half-heartedly used a design with a smallish external fins (e.g. Thermaltake 350W) but I'm thinking of something much chunkier here, and ideally as an optional bolt-on extra.

[ryboto]

I've got a quad core(Q9400) at 3.0ghz and an HD3870 all on a 220W Dell brick, which is external. There are other bricks out there. We have external power supplies, and combined with a Pico or PW-200 series internal DC-DC converter, you've got an internally space saving solution. Price isn't terrible, only trouble is that it's still highly DIY.