Cool quiet fast PC in hot dusty house - Comments and PSU advice needed

[Charlie King]

My current PC got far too hot last summer, and is due for replacement
anyway, so I'm planning on rebuilding.

I'm looking to achieve a sensibly quiet PC that will perform reliably
in a house that gets dusty (it's being restored), and hot (45 deg C
outside last summer, but rather cooler indoors)

I'll keep my case - it's a Chieftec Scorpio, and I'm happy with it,
but I'm replacing all the fans with Noiseblocker Ultra Silent Fan S4's
with BoogieBug anti-dust filters - two intake in the front, two
exhaust (not including PSU) at the back, and one intake in the side
that blows at the CPU.

The rest of the rig:

Motherboard ABIT AN7
CPU AMD Athlon XP3200+ Barton 400Mhz FSB
RAM Corsair XMS 512 Mo DDR PC3200
GPU Asus Radeon A9800XT-TVD /256
HDD's 2 x Seagate Barracuda 7200.7 - 160G - SAT
Heatsink Thermalright SP97 + Noiseblocker Ultra Silent Fan S4

(plus a LiteOn CDRW, and a Creative SB Live 5.1)

My first problem is the PSU - as has been mentioned here before,
finding good, in dependant reviews that cover noise and power output
for PSUs seems tricky.

So far I've narrowed it down to:

Enermax EG465AX-VE(G) FMA (460w 'Super Low Noise')
Zalman ZM400B-APS (400w)
Q-Technology SIL-Q400 (400 Watts - Double Papst Fan)

....but I need to be sure that there's enough good power for all the
kit above and that the noise level will be satisfyingly low.

Also, how noisy will the Radeon 9800XT be, and is there anything to be
done about that?

Finally, any general advice appreciated

Cheers

 

[jeffc]

I'm looking to achieve a sensibly quiet PC that will perform reliably
in a house that gets dusty (it's being restored), and hot (45 deg C
outside last summer, but rather cooler indoors)

I'll keep my case - it's a Chieftec Scorpio, and I'm happy with it,
but I'm replacing all the fans with Noiseblocker Ultra Silent Fan S4's
with BoogieBug anti-dust filters - two intake in the front, two
exhaust (not including PSU) at the back, and one intake in the side
that blows at the CPU.

Not familiar with the case, but make sure you seal any cracks or air vent
holes anywhere but at the intakes you want. I might even leave off one of
the rear exhaust fans so that the internal pressure doesn't get too low. If
it does air will be sucked in every nook and cranny in your computer,
bypassing your filters, unless it's sealed airtight.

 

[Wooducoodu]

the noiseblocker fans are not quiet, even the slower S2s make more noise
than a panaflo L1A. i'd use panaflo L1As or nexus real silent fans for the
case fans and maybe a panaflo M1BX for the CPU if you really need the extra
cfm.

the seasonic super silencer or enermax "noisetaker" are both good, quiet
PSUs and the most efficient currently available.

those little 40mm video card fans can be really annoying. take a look at the
sapphire 9800XT ultimate.

also, the samsung SP1614Cs are quieter than the seagate hard drives.

 

[Isaac Kuo]

I'm looking to achieve a sensibly quiet PC that will perform reliably
in a house that gets dusty (it's being restored), and hot (45 deg C
outside last summer, but rather cooler indoors)

For an example of a serious homebrew case mod which combines
air filters with muffling, see:

http://www.silentpcreview.com/article103-page1.html

I'll keep my case - it's a Chieftec Scorpio, and I'm happy with it,
but I'm replacing all the fans with Noiseblocker Ultra Silent Fan S4's
with BoogieBug anti-dust filters - two intake in the front, two
exhaust (not including PSU) at the back, and one intake in the side
that blows at the CPU.

With the increased air resistance of the filters, all those
fans will probably make quite a bit of noise in order to
acheive good airflow. I'd personally go with a more extreme
"box in box" air filter modification using a couple central
air conditioning air filters forming two side walls to a
large box within which the computer case resides. Air gets
sucked in one side and blown out the other:

BACK
_________

: >
:___ >
| | >
| | > TOP VIEW
| | >
| | >
|___| >
: >
______:__>

FRONT


A couple walls attached to the sides of the computer case
extend to the outer box walls to guide air through the
computer case. Here, the air filters have a huge cross
sectional area, so they won't introduce excessive air
resistance. Also, the large area will allow longer
periods of time between filter replacements.

The rest of the rig:

Motherboard ABIT AN7
CPU AMD Athlon XP3200+ Barton 400Mhz FSB
RAM Corsair XMS 512 Mo DDR PC3200
GPU Asus Radeon A9800XT-TVD /256
HDD's 2 x Seagate Barracuda 7200.7 - 160G - SAT
Heatsink Thermalright SP97 + Noiseblocker Ultra Silent Fan S4

(plus a LiteOn CDRW, and a Creative SB Live 5.1)

My first problem is the PSU - as has been mentioned here before,
finding good, in dependant reviews that cover noise and power output
for PSUs seems tricky.

The definitive place to go is:

http://www.silentpcreview.com/

These guys are the only ones I know of who even use testing
facilities suitable for measuring low noise levels. If
you look at the PSU reviews, you'll see all the data you
need and more regarding noise, voltages, efficiency,
and temperature performance.

The selection of reviewed power supplies is limited, but
I'd stick with one of them because that's really the only
way to know what you're getting.

So far I've narrowed it down to:

Enermax EG465AX-VE(G) FMA (460w 'Super Low Noise')
Zalman ZM400B-APS (400w)
Q-Technology SIL-Q400 (400 Watts - Double Papst Fan)

At silentpcreview, there are reviews of models similar
to those you've picked. There may be some important
differences, though.

...but I need to be sure that there's enough good power for all the
kit above and that the noise level will be satisfyingly low.

Also, how noisy will the Radeon 9800XT be, and is there anything to be
done about that?

There are a number of discussions about this on
silentpcreview's VGA forum. My personal solution would
be to get a fanless Radeon, but there are other cooling
options. Since your temperature environment is challenging,
perhaps Zalman's ZM80A heat pipe based cooler would be
good. It is fanless, but it has a huge surface area
thanks to its heat pipe routing heat to massive heat
sinks on both sides of the card. I use one to cool a
Pentium III 550 (not its original intended purpose).

Finally, any general advice appreciated

Since your environment is hot, you want lots and lots of
airflow for reliability. Sorry, but this is going to
mean noise. I'd personally ditch the existing case
side walls and front face, replacing the left wall with
a custom wall like this:

BACK
_________

: >
:___ >
: . >
: . > TOP VIEW
: . >
: . >
:___. >
: >
__:______>

FRONT

The custom left side wall extends all the way across the
filter box, and features 3 intake fans--each on blowing
straight onto a separate component. One fan blows onto
the CPU heatsink via a duct, one fan blows onto the GPU
heatsink (Zalman ZM80A), and one fan blows onto the
hard drives. All other fans are removed except for the
PSU fan. In this design, airflow is generally from the
left side to the right, although the motherboard is a
huge slab-like obstruction which air has to find its
way around. Removing the front and right sides of the
case will help give the air more ways to escape.

Note that the front openings have become exhausts with
this design, rather than intakes.

Isaac Kuo

 

[Charlie King]

On Fri, 2 Apr 2004 13:17:24 +0100, in
<[email protected]>
(alt.comp.hardware.pc-homebuilt) "nightic"

Can't say that I'd recommend the SP-97 for a quiet cooling solution (having
owned one until quite recently).
While it is likely still the finest 'performance cooling' heatsink for
Socket A, it's design (tight fin structure) isn't sympathetic to low CFM
fans with a low output pressure.
IMHO for your needs the Zalman CPNS7000A-Cu would be a better bet.

I did think about the Zalman, but Zalman's site lists it as
incompatible with the motherboard.

 

[Charlie King]

Can't say that I'd recommend the SP-97 for a quiet cooling solution (having
owned one until quite recently).
While it is likely still the finest 'performance cooling' heatsink for
Socket A, it's design (tight fin structure) isn't sympathetic to low CFM
fans with a low output pressure.
IMHO for your needs the Zalman CPNS7000A-Cu would be a better bet.

Following your, and a couple of other folks', comments, I've started
thinking that I'd be better off with an Asus A7N8X-E Deluxe
motherboard, which would allow me to go with the Zalman CPNS7000A-Cu
fan, and save about 4 euros into the bargain

Any comments on the Asus A7N8X-E Deluxe?

 

[nightic]

Following your, and a couple of other folks', comments, I've started
thinking that I'd be better off with an Asus A7N8X-E Deluxe
motherboard, which would allow me to go with the Zalman CPNS7000A-Cu
fan, and save about 4 euros into the bargain

Any comments on the Asus A7N8X-E Deluxe?

It's a good board, owned one myself a while back - fully featured though
really not for the overclocker.
My money would be on the DFI Ultra Infinity, especially if you plan on
overclocking.
This would still allow use of the Zalman and would save even more money.

 

[jeffc]

Charlie King <[email protected]> wrote

For an example of a serious homebrew case mod which combines
air filters with muffling, see:

http://www.silentpcreview.com/article103-page1.html

Umm, you lost me there. That filters the air LEAVING the PC. I don't get
it.

 

[Dorothy Bradbury]

in a house that gets dusty (it's being restored)

So industrial environment - continual brick/wood/cement dust

(45 deg C outside last summer, but rather cooler indoors)

Ambient of 45oC is not fun to design for re lower delta-T between
the ambient air & the object to be cooled by air velocity over it.

Personally, I'd do the following:
o Wooden box to enclose any PC case
o Door with simple rebate & draught excluder
o A/C filter panel inset into door, 2" thick, cardboard frame, 5 Euros
---- ask for the resistance (Pa) v velocity (m/sec) at Free / 50% clogged
---- since resistance (Pa) rises with air velocity, you use a big filter
o Rear exhaust fan 150/172mm 12/24V rear fan run at 12/24V
---- want a Pa figure high enough to retain ok cfm at filter 50% clogged
o Foam airflow-bypass-preventer around the PC in the box
---- forcing exhaust fan to pull air out thro the case vs bypassing it

Static resistance v airflow v ambient is the problem here.
So perhaps use an entire side as filter area - eg, 18"x18", so you are
minimising static resistance, boosting airflow & allowing 1x 172mm fan.
Just requires a change in the location of the foam to prevent bypass.

You can't use normal low-profile tubeaxial fans in this application:
o You are using a filter + dusty environment
---- Filter resistance is in the 10s of Pa + clogging relatively quick
o Your ambient temperature is very high
---- so high airflow is required despite losses due to filtration
o Small 38mm-depth tubeaxial do a few 10's Pa at 0cfm
---- your filter will offer a few 10's Pa whilst maintaining 100cfm

Papst & Comair Rotron do 150/172mm fans that will suit, and
you can often find them at good prices on Ebay. You would have
quite a struggle - or noise - using 120x38mm fans to achieve same.

The bigger you can make the filtered intake, the longer it will take
to clog in a such a very dusty environment & easier to get high cfm.

 

[Al Dykes]

So industrial environment - continual brick/wood/cement dust


Ambient of 45oC is not fun to design for re lower delta-T between
the ambient air & the object to be cooled by air velocity over it.

Personally, I'd do the following:
o Wooden box to enclose any PC case
o Door with simple rebate & draught excluder
o A/C filter panel inset into door, 2" thick, cardboard frame, 5 Euros
---- ask for the resistance (Pa) v velocity (m/sec) at Free / 50% clogged
---- since resistance (Pa) rises with air velocity, you use a big filter
o Rear exhaust fan 150/172mm 12/24V rear fan run at 12/24V
---- want a Pa figure high enough to retain ok cfm at filter 50% clogged
o Foam airflow-bypass-preventer around the PC in the box
---- forcing exhaust fan to pull air out thro the case vs bypassing it

Static resistance v airflow v ambient is the problem here.
So perhaps use an entire side as filter area - eg, 18"x18", so you are
minimising static resistance, boosting airflow & allowing 1x 172mm fan.
Just requires a change in the location of the foam to prevent bypass.

You can't use normal low-profile tubeaxial fans in this application:
o You are using a filter + dusty environment
---- Filter resistance is in the 10s of Pa + clogging relatively quick
o Your ambient temperature is very high
---- so high airflow is required despite losses due to filtration
o Small 38mm-depth tubeaxial do a few 10's Pa at 0cfm
---- your filter will offer a few 10's Pa whilst maintaining 100cfm

Papst & Comair Rotron do 150/172mm fans that will suit, and
you can often find them at good prices on Ebay. You would have
quite a struggle - or noise - using 120x38mm fans to achieve same.

The bigger you can make the filtered intake, the longer it will take
to clog in a such a very dusty environment & easier to get high cfm.

Dorothy sounds like she knows what she's talking about. All I can add
is that you should set up overtemp alarms. Your ambient (45C) is so
close to the conservative MAX that you might fry the system as soon as
a fan fails.

I use these audio alarms that screem when heated to 110DegF;

http://www.pcpowercooling.com/products/cooling/alert/index.htm

45C is 113F. On the first hot day, with a clogged filter the alarm
might save your machine. I like to put these gadgets next to my disk
drives. Most of the spec sheets for disk drives I've looked
at say disks like to be kept below 115F.

45C is hot enough that I'd consider running the CPU at a lower clock
speed, which make it run cooler. Maybe the same thing for the video
card and the bridge chips, if your mobo allows it.

 

[ToolPackinMama]

So industrial environment - continual brick/wood/cement dust

Perhaps an ionizer in your PC room would help? I have one, and they
clean the air silently. It's not just good for the PC, it's good for
you.

 

[Tim Auton]

Perhaps an ionizer in your PC room would help? I have one, and they
clean the air silently. It's not just good for the PC, it's good for
you.

Not sure if an ionizer would help that much with the large quantity of
large dust particles building work creates, but generally I think
they're great. Put it on a piece of paper though, as the crap it pulls
out of the air will accumulate on whatever you put it on.


Tim

 

[Isaac Kuo]

in message news:<[email protected]>...

Umm, you lost me there. That filters the air LEAVING the PC. I don't get
it.

Umm, you lost yourself there. It filters the air ENTERING the PC.
You don't get it.

That article explains in good detail how the mod works and
how he constructed it.

Isaac Kuo

 

[Kevin Lawton]

Sorry I missed the beginning of this thread (ISP problems) and I think it
might have come up before, but anyway:
The solution I use to keep the inside of my PCs clean in a dusty environemt
is quite cheap and simple.
In factories making things like cameras or watches, which require clean air,
they filter all the coming in to the assembley rooms and have a very slight
positive pressure so that clean air flowing out stops any dirty air getting
in. You can do the same with a PC case by simply arranging for two things:
1) Make sure that air is drawn into the case by intake fans more strongly
than it is sucked out by exhaust fans.
2) Use filters over the intake fans and keep them clean.
Most PSUs have a fan which exhausts air from the PC case, it is inadvisable
and unnecessary to mess with this.
Most PC cases have provision for mounting at least two 80mm fans - either
one in front and one at the back or two at the front. Sometimes the cut-outs
in the case can accept larger fans - even better. Filters which mount on the
outside of the case using the fan mounting screws are available widely and
cheaply, and the outer part of the shell easily unclips to clean the filter
element. Most PC cases have many holes in them. Using this arangement will
ensure that air flows out through these holes so that dirty air is not
sucked in.
Using bigger fans, or more fans, carries the added bonus that you can reduce
the fan speed to cut down the noise and still get adequate air flow. You
only need a steady movement of air in most cases, not a massive blast. The
filters may slow the air flow down, but only very slightly. They will also
serve to reduce the noise from the fans a little.
Hope this helps - it works for me.
Kevin.

|| Dorothy Bradbury wrote:
|||
|||| in a house that gets dusty (it's being restored)
|||
||| So industrial environment - continual brick/wood/cement dust
||
|| Perhaps an ionizer in your PC room would help? I have one, and they
|| clean the air silently. It's not just good for the PC, it's good for
|| you.
|
| Not sure if an ionizer would help that much with the large quantity of
| large dust particles building work creates, but generally I think
| they're great. Put it on a piece of paper though, as the crap it pulls
| out of the air will accumulate on whatever you put it on.
|
|
| Tim

 

[jeffc]

Umm, you lost yourself there. It filters the air ENTERING the PC.
You don't get it.

Isn't that what I just said? I don't get it? Alright, on closer inspection
I see the intake and exhaust are right next to each other. This doesn't
look like a very good design to me. Have you ever seen cars with rear
speakers just sitting on the back deck? You know why they sound like crap?
Because they can't generate any bass. They can't generate bass because
there's no baffle. That means that when the speaker pushes out, it simply
sucks air from the other side of the speaker. It doesn't generate a "solid"
air wave. This fan design is similar in theory. You've got air blowing
into the computer, and right at the same spot you've got air blowing right
back out. Most of that air simply goes in and then back out the power
supply, not generating nearly the same amount of airflow over the
motherboard as if the intake were in the front bottom of the computer case.

 

[Isaac Kuo]

Isn't that what I just said? I don't get it?

If you don't get it, then please try reading the article
linked above. It explains everything, with plenty of
pictures.

Sorry, I just didn't see the need to explain how bluefront's
case works seeing as he's already done an excellent job of
it in the above link. Unlike my usenet posting, his web
site article can include helpful explanatory pictures (and
it does).

Alright, on closer inspection
I see the intake and exhaust are right next to each other. This doesn't
look like a very good design to me.

They aren't next to each other.

The intake is at the top rear. The exhaust is at the front
bottom. This exhaust goes downward into the big huge
muffler that the case sits on top of. The exhaust isn't
anywhere near the intake.

You've got air blowing
into the computer, and right at the same spot you've got air blowing right
back out. Most of that air simply goes in and then back out the power
supply, not generating nearly the same amount of airflow over the
motherboard as if the intake were in the front bottom of the computer case.

Well, that might be true except that it's not.

The main airflow of the case goes from the top rear intake
to the front bottom exhaust.

Just curious, you did see the huge wooden box with a tailpipe
that the case is sitting on top of in the pictures, right?
What did you think it was?

Isaac Kuo

 

[jeffc]

If you don't get it, then please try reading the article
linked above. It explains everything, with plenty of
pictures.

Sorry, I just didn't see the need to explain how bluefront's
case works seeing as he's already done an excellent job of
it in the above link.

If it does what you say it does, then no, he hasn't. Look at the link
again. In the rear of the case, there is a filter over one of the fans
(what do you think that foam piece is covering?) Now are you going to tell
me he's filtering the air LEAVING the computer? If so, that is WEIRD, and
even so what is the point of that bizarre filter design? That leads me to
believe that filter is filtering INPUT air. If so, then are you saying the
PSU blows air IN? I doubt it. Therefor, you've got a fan blowing in
directly below the PSU fan blowing out. That's not a very good design. If
this is not the case, then please explain, because if I'm wrong then that
diagram is way too confusing.

 

[Parish]

If it does what you say it does, then no, he hasn't. Look at the link
again. In the rear of the case, there is a filter over one of the fans
(what do you think that foam piece is covering?) Now are you going to tell
me he's filtering the air LEAVING the computer? If so, that is WEIRD, and
even so what is the point of that bizarre filter design? That leads me to
believe that filter is filtering INPUT air. If so, then are you saying the
PSU blows air IN? I doubt it. Therefor, you've got a fan blowing in
directly below the PSU fan blowing out. That's not a very good design. If
this is not the case, then please explain, because if I'm wrong then that
diagram is way too confusing.

Look at the third picture down where he's holding a cardboard template.
See the line drawn on the card that goes from between the two fans up?
That's a divider. The area below that is the intake for the bottom fan;
the area above is the exhaust for the PSU fan, the divider deflecting
the airflow upwards.

Now look at the next page, second picture, you can see the divider (the
photo is looking from underneath the duct), but it's not too clear as
he's covered it inside and out with soundproofing felt.

------+ |
| /|
| / |
PSU | / |
| / |
| / |
|/ |
| /|
| / |
IN FAN| / |
| / |
| / |
|/^ |
|
|
FILTER

Parish

 

[Rob Morley]

If it does what you say it does, then no, he hasn't. Look at the link
again. In the rear of the case, there is a filter over one of the fans
(what do you think that foam piece is covering?) Now are you going to tell
me he's filtering the air LEAVING the computer? If so, that is WEIRD, and
even so what is the point of that bizarre filter design? That leads me to
believe that filter is filtering INPUT air. If so, then are you saying the
PSU blows air IN? I doubt it. Therefor, you've got a fan blowing in
directly below the PSU fan blowing out. That's not a very good design. If
this is not the case, then please explain, because if I'm wrong then that
diagram is way too confusing.

Air intake is via the aperture at the rear below the PSU - it is ducted
over the CPU heatsink, and then leaves the case either through the PSU
or through the filter box underneath. This is a departure from standard
practice because the inside of the case is at reduced pressure, and some
of the exhaust is via the bottom front of the case. So it goes against
convection within the case, and the air box and PSU are fighting each
other for air. I reckon it's an ill-conceived design, but it's quite
possible that it keeps everything cool and quiet. I wouldn't do it that
way though.

 

[jeffc]

Look at the third picture down where he's holding a cardboard template.
See the line drawn on the card that goes from between the two fans up?
That's a divider. The area below that is the intake for the bottom fan;
the area above is the exhaust for the PSU fan, the divider deflecting
the airflow upwards.

That's exactly what I said. I got flamed by Isaac Kuo who said I didn't get
it, and "They aren't next to each other. The intake is at the top rear. The
exhaust is at the front bottom." I don't know what Isaac is looking at, but
it doesn't seem to be what we're looking at. So I repeat what I said - it's
not a very good design. Just like you need a baffle for a loudspeaker
(don't set woofers sitting bare on your rear car deck), likewise you should
not be intake and exhaust fans right next to each other. They have a
tendency to cancel each other out and you get much reduced airflow over your
motherboard.