Is it possible to build a silent computer, without fans at all? What case should I buy?

On Feb 12, 8:59 am, Ashton Crusher wrote:
I went ahead and put the duct in since it was there. Kind of a pain
but it's not like I will be in there all that often. I'm pretty
impressed by the basic design of the case, it's easy to install stuff
into and can't beat the price.

Thanks Ashton, Ken and GT for your replies!

On Wed, 14 Feb 2007 20:00:29 -0600, "Ken Maltby"
wrote:


Your "Exception" is the rule for such "Passive CPU
coolers" and more and more for those with a fan as
well. Was it an accident that you snipped out your
MB "laying out in a room"challenge that I was replying
to in my paragraph you quote above.

I'm snipping things out because it isn't my system, I'm not
burdened with continually pointing out what you have failed
to address, nor that none of your arguments replace the
obvious requirement of qualifying a cooling subsystem- to
accurately measure ALL parts that heat up to any significant
extent, but apparently argument is a replacement.

With lesser heat retained in the chassis due to water
cooling, you could easily have the same temps with a much
lower chassis airflow, but you wanted to just ignore some of
them so you can arbitrarily claim no fans is ok. OK in the
short term, perhaps - and I never claimed it wasn't viable
for a shorter lifespan.

These are not only issues relevant when one does away with
fans. It's also a regular factor in quiet system cooling
WITH fans, to assess how the changes in the cooling
subsystem effect ALL parts, not just the hottest that have
their own fan, waterblock, etc. ... but you don't want to
consider this, because the magic water block must do
miracles even to parts it doesn't cool.

You are trying hard to stretch negligable things into an
argument. There is not nearly high enough surface ara on
the waterblock, the waterblock is HEATED from the part it is
cooling, and the temp difference between chasssis ambient
and waterblock is not only minor, but the waterblock
would've even been HOTTER than the case if only you had a
fan in the system, so you somewhat have it backwards.


The only way your statement could possibly make the
slightest bit of sense, would be if you believe that a fan
could/would lower the MB temp. to a point lower than
the temp. of the water in the Watercooling system.

No, it's also considering implementation into a system. The
water in the cooling system isn't necessarily at a higher,
or lower temp than the heated motherboard components (those
not cooled by water blocks). It doesn't necessarily matter
how the water temp relates to the ambient temp immeidately
around the heated parts. Without a fan, the parts
themselves are the heat source, they are creating this
higher ambient temp. With a fan removing heat from the
system, the ambient air temp is already lower, PLUS the
active airflow on the parts, both contribute to even lower
temps on these non-waterblocked parts, and the copper on the
board that is sinking away heat from some of them.




Which again goes to show that you have no experience
or understanding of watercooling, whatsoever. (Not
that this has prevented you discounting the effects of
watercooling the main heat sources within a system,
upon the thermal environment for the other components.)

You still don't get it. We could take the CPU and other
water cooled components out of the system ENTIRELY, have
zero heat produced by them, and remove the waterblocks too
of course, but rig the board so that it passes the same
amount of power to the remaining parts on the board, and an
external (outside the case and far enough away to not
significantly effect room ambient temp) load to replace the
load that was the now-removed parts. The remaining parts in
the system are creating heat, heat that is raising their
immediate ambient temp of board, epoxy casing, parts higher
up on the board if vertical, etc, without active airflow in
the chassis.

Where did you think this heat would go? It builds up,
unless your room fan is so strong it is effectively
replacing a chassis fan, but that's not really a passive
system then, because it still relies on external fan-forced
airflow.




This is nonsense. It is beyond ridiculous to think
measurement of a heatsink casually fastened across muliple
FETS with the typical poor interface used by a motherboard
manufacturer could be even close to usable data.

If you want to keep trying to make that point, you need to
explain how enough heat can make it through the FETs
packaging to be carried away by the small amount of moving
air that actually crosses the exposed surface, to prevent a
damaging rise in the temp of the parts, but that not enough
heat gets though to indicate higher temps in the part. Or to
be properly cooled by direct contact with a waterblock.

The primary heat path of the FET is through the copper on
the board, which of course rises in temp based upon how much
airflow it has. The hotter it gets, the lower the thermal
delta and the lesser the rate of heatsinking.

Why you aren't getting an indication of higher temps is as
I'd already mentioned, you can't measure the base of a OEM
slapped-on heatsink draped across a bunch of different SMT
parts, interfaced with a variably effective thermal
interface (depending on who applied it, quality of interface
material present, etc) then all this on top of the
non-primary heat path, through the encapsulating epoxy.

Direct, *good* contact (DIY, not just accepting a factory
heatsink installation) with the sink or waterblock will
help, certainly some of the heat is being removed through
that epoxy, and it is good to keep it from getting too hot,
but nevertheless it is not the primary heatsinking path, it
is far lower efficiency. It would be a bit like putting a
single video card heatsink on the back of the video card
instead of the front.





The facts are right in front of you, but you deliberately
refuse to collect them. Same with capacitors, you don't
actually measure and compare both ways, instead dodging and
weaving around the inescapable truth.


No, I can't compare failure rates or reduced lifespan of the
capacitors in my watercooled system, unless and until there
is a failure.

Actually that is my complaint with your observations. You
have obviously never had any watercooling experience. Yet
you keep claiming that what I observe is invalid, that there
are parts running hotter, even though I observe no such thing
(in fact quite the opposite).

Then where did the heat go? The parts you dismiss aren't
producing less heat. The heat produced doesn't disappear,
it remains in the system for longer through a less effective
thermal path out of the chassis when there is no airflow,
resulting in rising chassis temp. If this is not the
situation then you have the case far more open than you have
described and the room fan blowing quite a bit into it. If
that is the situation and you are content with it, ok, but
how is it really a passive system if it has this room
airflow requirement?




I've measured capacitors that were 20C hotter in a passive
system,

What "Passive" system, hotter than what? To a system with
Fans, I take it. If by "Passive" you mean you just removed or
disabled the fans, for some measurements, and just let it then
heat up in a closed box, then I might believe your results. If
I actually could believe you ever took any measurements.

BUT, one thing is sure, you weren't making a comparison
between a Watercooled system (Which YOU don't have)
and one of your fan cooled systems.

Actually I was, you have somehow made another wild leap to
support your argument, because if I even start to supply
information you can't accept it- which is why I had already
suggested your measurements were necessary. But enough time
spent, if you can't resolve that heat doesn't vanish from
parts consuming current, that it is removed slower without
airflow, then all the direct measurements of capacitors or
chassis temp in the world won't matter because you reject
anything that doesn't agree with your preconceived notion.

If I had meant "just pull all fans", it would have been a
dissimilar situation and I wouldn't have bothered to mention
the caps being hotter. Perhaps I should have described the
scenario at length, but it would not be directly applicable
as distance to other parts (particularly the FETs) have a
direct bearing on cap temp in a fanless system, and your
board is not laid out the same... it is close enough to be a
factor, but it was only one example, but your parts do
create heat and do need the same types of measurements but
instead you continually just try to think through it with a
dismissal attitude instead of seeing there is more to it
than just 3 or 4 components having waterblocks.

I think we have both wasted enough time on this thread. So
I opt-out.

On 14 Feb 2007 16:19:21 -0800, "
wrote:

On Feb 14, 10:41 pm, kony wrote:
On 12 Feb 2007 16:01:40 -0800, "

wrote:

what makes/models have you tried?

Every single one of them runs hot. The remaining question
is how long you need it to work.


how hot is hot. You didn't check, ok.

Every one dies early?

You mention "a few years". Well, what's the normal lifetime of a power
supply? Probably not more than a few years anyway.


This is a distinction, yes I meant long term use, not just a
few days of runtime. Just like you wouldn't be able to
predict the second your car might seize up if you redline it
continuously till it fails, I can't put a day, week, month
on when any given passive psu will fail, there are too many
variables to do this. I would expect most to fail within 3
years if ran at their rated max load, but any other system
is another variable among many.

We can instead see from all reviews that the internal temps
are higher, and it is established fact that components do
fail at an accelerated rate. These passive units do have
some unique 'sinking but they're not substantially different
when it comes down to discrete part specs.

A good PSU will last over a decade. I have quite a few that
have, AT PSU that run fine still in addition to early ATX.
What have we seen from other PSU running hotter? Failure in
months or a couple years, usually.

By the above (and below) I am considering one scenario only,
use of a passive PSU in a (either very close to, or
entirely) passively cooled case, no fan-forced airflow
through the PSU. Part of the reason for this is due to a
problem inherant with the passive psu, that most cases have
the rear exhaust fan which would result in air intake
through the back of the PSU, the heat from the PSU being
dumped into the case, then expelled out the back and this
again drawn up and back into the PSU for another cycle. If
someone where to mount only intake fans on the side and/or
front of the case, these passive PSU would fare (and effect
the system they're in) far more positively.


People buy new PSUs even without them dying.

Yes, that is one possibility, but does it mean the old one
was thrown away? Generally not if it was decent, it either
remains with the system as a whole or is reused. Certainly
there are exceptions but we have to at least consider the
typical situation, that a PSU is bought for a system and
stays with that system - then eventually it becomes the
first failure point (odds are), unless the motherboard had a
particular flaw like defective capacitors.

When considering an old 80486, it can't do the basic things
people expect - realtime video, audio, modern video
resolutions for typical 2D work with enough pixels that
everything doesn't look blocky in a windowed environment.

Now contrast that with what a Core2Duo and XXXX will be able
to do 10 years from now... it will take some less common
activity to make such a system undesirable for most common
uses, unless there are some revolutionary breakthroughs on
the next so-called "killer app", like maybe virtual reality,
but frankly I don't see it becoming more than a reason to
upgrade a video card in the next few years we'd hope a PSU
would last.



Bare in mind that many people buy new computesr every few years
anyway. Either because their MBRD dies, or because it isn't up to date
enough for them.

They don't generally throw away the old one, it still needs
a PSU. I wish I remembered where I saw it, but there is a
site online that did a survey about average system age, and
the average age is now close to 5 years... meaning a
substantial number of systems older than that. What was
available 4 years ago, in 2003?

nForce2 and Athlon XP,
http://www.tomshardware.com/2003/02/14/more_nforce2/
3GHz Pentium 4,
http://www.tomshardware.com/2003/02/...dr/page20.html

Frankly I think the survey I saw was off, I'm suspecting
the average systems belong to people not so exposed to
online surveys and are now older than 4 years. As
importantly, I know a LOT of people who when their system
did fail, had no desire to do anything except get their
present system working again as cheaply as (reasonably)
possible, if it wasn't their PSU that failed they had value
in it and wanted to continue using it.

Regardless, surely you know someone who would gladly accept,
even pay money for a 2+GHz Pentium 4 system? It's going to
need a working PSU? There is no real justification to the
idea that it's ok if parts die, they should always last
until the last person who would want to use a system, gives
up on it. That's going to be a long, long time for anything
built today, it will be a part failure causing a typical
system to be thrown away if not just laziness of the owner
to not make it available to anyone who might want it.

Making parts with shorter lifespans ultimately results in
increased garbage, unnecessary addition to landfills,
manufacturing pollution. Even when an original owner doesnt
want a product anymore, it is better that it still work.


And when doing that, new computers often use a new power supply
specification.

So you'd just throw away all old parts? Seems a bit of a
waste, unless you were assuming the parts died- the opposite
of what I advocate, to make choices that result in a system
continuing to work and have a potential purpose to
"somebody". Systems fast enough to run WinXP without
severe pain for email, office, web browsing, are now 8 years
old. That's all a lot of people use their systems for.


Around last year I started setting up P4s, they needed the 2x2 thing.
My old power supplies didn't have that. And I got a good deal on a
load of good quality new PSUs that had it.

I was buying PSU with 2x2 connectors well over 4 years ago,
in the Pentium 3 era but I don't recall the first... but one
of the earlier might've been an Antec PP303XP. It only had
15A on the 12V rail, but this was before CPUs came near even
100W TDP, which with a roughly 92% board VRM subcircuit
efficiency, would be under 9A, plenty of current left for a
handfull of fans and a couple drives.

What has changed? Mostly 12V current, if your older PSU had
enough you didn't need a new PSU, just an inexpensive
adapter. Soon thereafter we saw 400W+ PSU with 18-20A on
12V rails, and so on.



It's very odd that you say that every single one of them runs hot.

Not so odd, what did you think the purpose of the fan was if
not to remove that heat? "Hot" is relative though, I didn't
mean you can use it to fry eggs (but actually, you probably
could come close in some of them).



If that is your experience, why do you keep buying them? Or do you get
them for free?

I get most of my non-preferred parts (for free) after they
fail, but with the newer breeds of PSU you can find online
reviews where the passive unit reviews do have particular
attention paid to internal temp, as it is a pretty obvious
factor when the PSU is so costly and (fortunately) derated
so it looks better than most of a similar wattage that had
fans.



I doubt you fix peoples' computers where the people have fanless power
supplies.
If every single one of them dies, then this would be a serious problem
to look out for. If I found that, i'd have started a thread, giving
exact details.. seen if anybody else had similar experiences.

If you have a hot skillet on the stove and I told you that
every single egg you put in it will fry, do I have to cook
every single egg you have before you believe it?

Cause and effect. You are thinking in terms of unknown
variables on a PC computer component, while I am considering
known facts about parts lifespan, in particular electrolytic
caps... especially because the solid alternatives are so
incredibly costly in high capacitance values, I keep hoping
one of these very expensive passsively cooled PSU will be
built befitting it's high price, as a case with a lot of
holes or screens in it, $5 worth of upgraded parts and a
couple extended heatpipe sinks (if that) can't account for
the added retail cost.

So if you were able to keep track of all owners of a given
passive PSU, yes it would be fair to say that on average,
they have a significantly shorter lifespan in number of
years, because they are not keeping the shortest lived parts
as cool, not substituting the substantially higher priced
parts that would fare better over the long term, only what
is required for immediately stable operation and hopefully
the duration of a warranty (but given the high price, it's
bound to be factoring in a potentially higher RMA rate
during the warranty period as well).




I googled
thermaltake fanless power supply overheat

I didn't get horror stories. One guy said it worked fine so far(2
days).

You seem to be entirely missing the point.

the point is that at least he provided some data. You provided none.


It's not necessarily my burden to hunt down information you
could find for yourself, unless it's something really
obscure but with any model PSU you might consider, you have
the applicable search terms and can seek a reviewer who has
taken measurements but as importantly, is a 3rd party
without a bias. Then comes experience and context, seeing
the non-defective cap failures from elevated temp.

You have no idea how many bad caps I've thrown away from
junk brought to me. Not "defective" caps, just not the
right part for the environment it was in so it's too hot,
from ambient condition and/or ESR too high. Maybe you have
seen a lot of failed caps? If so, can we agree that heat
kills them? If we can't agree on that, I suggest you head
over the badcaps.com and wander around for awhile, or read
the major cap manufacturers spec sheets and technical
guides.

There is nothing that changes the situation in a passive
PSU, unless they start building them with more appropriate
parts. If you have one you are considering, by all means do
look up the specs on the parts so you can see whether
appropriate changes were made.




yeah but given what you said, for all we know, they could die in an
instant.
At least now we know somebody had them work for 2 days, it's an
improvement on your data!


Not an instant, I expect that the majority will last a
couple years, but it's a large variable how positively or
negatively pressurized a case is from other fans (if
present), how heated that case is if there aren't any fans
in it, the room ambient temp, system load average as well as
peaks, hours of on-time. Just as every specimen of any
brand and model won't die at the same time, we can expect
some of the passive units to live quite a bit longer than
others, and never have any overheat-shutdown problems in the
interim that reviewers have caused.

Ultimately I am suggesting that you read some reviews if you
hadn't already, but also to consider that running a PSU for
a few hours is not any qualification of fitness for longer
term use. Resist trusting a reviewer's tendency to try to
judge fitness (especially considering I had never claimed
you couldn't run a system for a shorter period from one) and
just look at data, and ratings. A PSU has to live up to
them, that's the whole point of ratings, and if it does, how
long it will last.

If you really feel you would end up throwing away a power
supply after 4 years, maybe a passive unit is a reasonable
choice for you, if you are sure your system load on it is
low enough. It isnt really necessary though, any PSU can
have the fan running so slow it is not easy to hear if
higher temps are acceptible.

"kony" wrote in message
news
On 14 Feb 2007 16:19:21 -0800, "

To save the Internet bandwidth I will cut up and summarize
Kony's rambling circular arguments, that make it a 13KB,
post. His whole post is there for any willing to slog through it.


We can instead see from all reviews that the internal temps
are higher, and it is established fact that components do
fail at an accelerated rate.

Again, I'd like to read some of the specific reviews you
claim to have read. The ones you claim as a source for
your statements. Surely if "all reviews" are your quoted
source, you can provide ONE for us to check out?

What was
available 4 years ago, in 2003?

nForce2 and Athlon XP,
http://www.tomshardware.com/2003/02/14/more_nforce2/
3GHz Pentium 4,
http://www.tomshardware.com/2003/02/...dr/page20.html


See you can post a link to a "review" (it has nothing to do with the
issues raised in this thread, but it is evidence that you know how to
do it.)


wrote:
If that is your experience, why do you keep buying them? Or do you get
them for free?

I get most of my non-preferred parts (for free) after they
fail, but with the newer breeds of PSU you can find online
reviews where the passive unit reviews do have particular
attention paid to internal temp, as it is a pretty obvious
factor when the PSU is so costly and (fortunately) derated
so it looks better than most of a similar wattage that had
fans.


We could find reviews, but we want to see the ones you keep
claiming as support for your statements. It is apparent the links
I posted provided you with some understanding of the "Derating"
concept. So can't you post some, I mean you must have kept
at least a few of the URLs, of these "all reviews".


So if you were able to keep track of all owners of a given
passive PSU, yes it would be fair to say that on average,
they have a significantly shorter lifespan in number of
years, because they are not keeping the shortest lived parts
as cool, not substituting the substantially higher priced
parts that would fare better over the long term, only what
is required for immediately stable operation and hopefully
the duration of a warranty (but given the high price, it's
bound to be factoring in a potentially higher RMA rate
during the warranty period as well).


Don't you get dizzy arguing in circles like that?


wrote:
I googled
thermaltake fanless power supply overheat

I didn't get horror stories. One guy said it worked fine so far(2
days).

You seem to be entirely missing the point.

the point is that at least he provided some data. You provided none.


It's not necessarily my burden to hunt down information you
could find for yourself,

Unless, you are trying to make it prop up your arguments.

A PSU has to live up to
them, that's the whole point of ratings, and if it does, how
long it will last.

Hey, does that mean you finally agree that if a PSU maker
rates a PSU for 120,000hrs it should operate for at least
those rated hours - NO MATTER IF IT USES FANS or
NOT? (or runs hotter than any other PSU, or not? Not
that I'm saying a passively cooled PSU needs to run hotter,
much less so hot as to cause any reduced lifespan.)


I must of read too much of Kony's post, I need to go
make a cup of coffee.

Luck;
Ken