Seeking thermally engineered case

[alweiner7]

I've been searching the Usenet archives for information pertaining to
cases which provide good cooling. (The case reviews I've read don't
discuss thermal design). One theme that has emerged from this search is
that in many case designs, the front air-intake grill is undersized and
it substantially interferes with airflow. A preferred case design would
be a wire front air-intake grill with a surface area comparable to that
of the front case fan. Is there a mid-tower or full-tower ATX case
available that has this preferred design?

In my Usenet search, I've found that some people achieve this preferred
case design by taking an off-the-shelf case and cutting out the
supplied grill using a nibbler. I'm mechanically unskilled so case mods
are not practical for me.

The Intel-inspired "thermally-advantaged" case design meets my case
cooling objective. It achieves this by using a "chassis air guide" (AKA
duct). I have a reservation about this approach. I have the impression
that a case which is "thermally advantaged" for one ATX motherboard
model may not be "thermally advantaged" for a different ATX motherboard
model. Is my reservation justified?

BTX might meet my cooling objective, but from what I've read on Usenet,
BTX doesn't show signs of becoming widely adopted.

My expected cooling requirements are modest. My computing needs would
be met with a 600 MHz (0.6 GHz) CPU, integrated video, two IDE hard
disk drives, and one or two optical drives. However, I want my system
to run cool in a 90 degree F room.

In the spirit of DIY, I want to select components that are well
engineered. I would like to select a case that is engineered for good
airflow.

 

[Rich Greenberg]

My expected cooling requirements are modest. My computing needs would
be met with a 600 MHz (0.6 GHz) CPU, integrated video, two IDE hard
disk drives, and one or two optical drives. However, I want my system
to run cool in a 90 degree F room.

With that slow a PC (can you even buy one that slow anymore?) don't
worry about ducts. The single fan on most power supplys is all you
need.

You don't need multiple fans or ducts until you get up into several
gigiHertz processors, especially if overclocked.

 

[johns]

That would be the Antec SLK1650B I've tested that
case against several others in cooling an AMD64 3000.
All the other cases let the cpu run at 48 to 54 C even
when I used a PCI slot fan close to the cpu. All the
other cases felt warm to the touch, and were noisy
because the fans ran at 4800rpm full on. The Antec
case uses a side port directly over the mobo and
cpu. That lets the cpu fan blow straight out of the
case, and that is the major source of case heating. In
that case, my AMD64s run 37 to 43 C, and the case
feels cool to touch. Also, the "smart" psupply uses
2500rpm fans which are quiet. The main case fan is
also a quiet 2500rpm fan, so the entire system runs
fairly silent. The Psupply is 350watt, but it supplies
21amps on the 12volt rail .. considerably higher than
a generic case ... so my current hogging ATI 9800
Pro video card is happy. The price for this case
runs all over from $55 to $120 depending on S&H.
I found the best deal at Mwave.com, but then I
also noted that ComUSA will sell the case alone
and "smart" psupply separate. Put a 450watt in it
for about $90 total, and you have a nice case. Also,
in my opinion, front porting fans are a waste ... it is
the side port that works because the cpu heat never
gets piped around inside the case. It blows straight
out the side port ... very important!

johns

 

[BBUNNY]

That would be the Antec SLK1650B I've tested that
case against several others in cooling an AMD64 3000.
All the other cases let the cpu run at 48 to 54 C even
when I used a PCI slot fan close to the cpu. All the
other cases felt warm to the touch, and were noisy
because the fans ran at 4800rpm full on. The Antec
case uses a side port directly over the mobo and
cpu. That lets the cpu fan blow straight out of the
case, and that is the major source of case heating. In
that case, my AMD64s run 37 to 43 C, and the case
feels cool to touch. Also, the "smart" psupply uses
2500rpm fans which are quiet. The main case fan is
also a quiet 2500rpm fan, so the entire system runs
fairly silent. The Psupply is 350watt, but it supplies
21amps on the 12volt rail .. considerably higher than
a generic case ... so my current hogging ATI 9800
Pro video card is happy. The price for this case
runs all over from $55 to $120 depending on S&H.
I found the best deal at Mwave.com, but then I
also noted that ComUSA will sell the case alone
and "smart" psupply separate. Put a 450watt in it
for about $90 total, and you have a nice case. Also,
in my opinion, front porting fans are a waste ... it is
the side port that works because the cpu heat never
gets piped around inside the case. It blows straight
out the side port ... very important!

Except that the CPU fans that I have observed blow into
the CPU not away from them....

 

[Matt]

I've been searching the Usenet archives for information pertaining to
cases which provide good cooling. (The case reviews I've read don't
discuss thermal design). One theme that has emerged from this search is
that in many case designs, the front air-intake grill is undersized and
it substantially interferes with airflow. A preferred case design would
be a wire front air-intake grill with a surface area comparable to that
of the front case fan. Is there a mid-tower or full-tower ATX case
available that has this preferred design?

The Antec SLK3700 comes close to your need, as its lower front intake is
very good. I notice it's on sale now at Newegg. Newegg also has a
new model SLK3000, which seems to be the SLK3700 with a different side
panel having a duct and a vent. It looks like those extra vents would
reduce hard-drive ventilation so as to increase CPU ventilation. I
guess the SLK3000 gives you more options because it's probably easy to
block off the extra vents, but I would be reluctant to sacrifice air
flow to the hard drives.

 

[David Maynard]

The Antec SLK3700 comes close to your need, as its lower front intake is
very good. I notice it's on sale now at Newegg. Newegg also has a new
model SLK3000, which seems to be the SLK3700 with a different side panel
having a duct and a vent. It looks like those extra vents would reduce
hard-drive ventilation so as to increase CPU ventilation. I guess the
SLK3000 gives you more options because it's probably easy to block off
the extra vents, but I would be reluctant to sacrifice air flow to the
hard drives.

That's the Intel "thermally advantaged" design, which is a side mount air
duct to the Prescott heatsink.

If you're worried about hard drive airflow, not sure why since the combined
PSU and rear 120mm fan should be plenty more than the HSF airflow, then put
in a front mount fan that's located right in front of the hard drive bays.

 

[Matt]

Matt wrote:


That's the Intel "thermally advantaged" design, which is a side mount
air duct to the Prescott heatsink.

The advantage is to the CPU.

If you're worried about hard drive airflow, not sure why since the
combined PSU and rear 120mm fan should be plenty more than the HSF
airflow,

Without the side-panel openings, practically all the air entering the
case has to flow through the front vent. With side-panel openings, much
less air comes in through the front vent.

then put in a front mount fan that's located right in front of
the hard drive bays.

Yes, just move the 120mm to the front vent. Or close off the side-panel
ducts.

 

[johns]

Except that the CPU fans that I have observed blow into
the CPU not away from them....

It reflects directly back up from the heat sink. It can't
blow "into" the cpu. I put my hand over the side port
and air is coming out, not in. That could be the 2 psu
fans, as they are much stronger. Regardless, the side
port is a winner. It works.

johns

 

[David Maynard]

The advantage is to the CPU.

Brilliant.

What was the clue? That it's ducted to the heatsink?

Without the side-panel openings, practically all the air entering the
case has to flow through the front vent. With side-panel openings, much
less air comes in through the front vent.

I am aware of that. Just how much air do you think a hard drive needs?

Yes, just move the 120mm to the front vent.

No, the 120 should remain in the rear. ADD a front mount fan if you think
you need one to cool a hard drive.

Or close off the side-panel
ducts.

I wouldn't get a 'Prescott' case unless I had a Prescott and, then, it
would be a bad idea to defeat the purpose of the thing,

 

[Matt]

Brilliant.

Aw shucks.

What was the clue? That it's ducted to the heatsink?

Trying to make the point that the side duct is disadvantageous to the
hard drives.

I am aware of that. Just how much air do you think a hard drive needs?

I don't know. Better too much than too little. The OP mentioned room
temps up to 90 F. His first paragraph indicates a concern for HD cooling.

No, the 120 should remain in the rear. ADD a front mount fan if you
think you need one to cool a hard drive.

I don't know why you want a fan in the back. To reduce dispersion into
the case of warm air coming off the CPU, I suppose. The OP is running a
600 MHz CPU.

 

[Matt]

It reflects directly back up from the heat sink. It can't
blow "into" the cpu. I put my hand over the side port
and air is coming out, not in.

Are you sure? What happens when you put a sheet of paper over the side
port?

What HSF are you using?

 

[David Maynard]

Aw shucks.


Trying to make the point that the side duct is disadvantageous to the
hard drives.

It's only 'disadvantageous' if there's an adverse effect but your
predilection to insist that all intake airflow must come over the hard
drive is an invalid assumption.

I don't know. Better too much than too little.

Well, not knowing is a sight bit different than accusing the case of being
'disadvantageous'.

The OP mentioned room
temps up to 90 F.

90F sets a floor as to how cool one can get it.

His first paragraph indicates a concern for HD cooling.

Without actual numbers for the specific fans I can only speculate but it
isn't unreasonable to imagine that the PSU fan can handle at least as much
airflow as the CPU heatsink, which leaves the entire 120mm fan drawing air
from other than the side port. (it won't get distributed that way but
it's sufficient as a 'volume capacity' estimate)

I don't know why you want a fan in the back. To reduce dispersion into
the case of warm air coming off the CPU, I suppose. The OP is running a
600 MHz CPU.

Forced rear exhaust is more efficient that forced front intake and less
perceived noise because of the location.

As for his CPU being 600 Mhz, as mentioned below, I wouldn't be buying that
case for it to begin with. Which was what I originally meant in mentioning
that the "thermally advantaged" side vent/duct was for the Prescott heatsink.

 

[Matt]

My computing needs would
be met with a 600 MHz (0.6 GHz) CPU

Unless I already had a good source for the motherboard and CPU and RAM,
I would spend an extra $100 for a new Athlon XP 2800+ setup or so.

 

[Allen Weiner]

Unless I already had a good source for the motherboard and CPU and RAM,
I would spend an extra $100 for a new Athlon XP 2800+ setup or so.

I'm the OP for this thread. Thanks everyone for your replies.

In my original post I didn't explain myself well with regard to my CPU. When
I wrote that a 600 MHz CPU would meet my needs, I was just trying to say
that I'm not doing gaming, overclocking etc. My current commercial computer
has a 600 MHz CPU and it meets my needs.
I have numerous other dissatisfactions with the PC which is why I want to
build a DIY system.

I haven't selected the components for my system yet. I'm starting with the
PSU and case. For a CPU, I will probably pick the multi-GHz Celeron du' jour
or something equivalent.


I want my DIY system to be able to run in a 90 degree F room and put minimal
thermal stress on any of the components (HDD, CPU etc).

An aspect of DIY that apeals to me is being able to have each component well
engineered, rather than accepting an assemblers compromises.

I'd like to pick a case that is well engineered from a cooling standpoint.
What I've read on Usenet is that a lot of cases are thermally impaired due
to inadequate front air-intake. I'd prefer not to spend money on a thermally
impaired case.

I'd like to pick a thermally well-engineered case even if my cooling
requirements don't mandate it.

I'm concerned that the "thermally advantaged" cases are CPU and/or
motherboard specific, but I haven't actually seen that stated anywhere.

 

[Matt]

I'm the OP for this thread. Thanks everyone for your replies.

This is worth a look:

http://arstechnica.com/guide/system/budget.html