I have always wondered if there are any heat benefits to just leaving
my case open. I unerstand that when the case is closed air is forced a
certain path. However, what if I removed both sides of the case?

My setup:
I have a hightower with an intake fan at the front bottom. Both case
sides have open grooves running the length of the side to let passive
air in. I also have the power supply with two exaust fans in series.
Then at the very top I added two 80mm fans pushing air out. So total I
have one intake and 3 exhaust fans. Given that I have 8 hard drives in
there, I'm guessing this baby is generating a lot of heat.

So I have considered just leaving the case sides completely off. Just
let the hot air move up and be replaced by colder air. I have also
considered making holes on the sides of the case and adding two 80mm
fans or perhaps a large 120mm fan. I am not one bit concerned about
noise as this unit is not where I can hear it.

Any suggestions?

jg

jg <juangarcia (AT) sacbeemail (DOT) com> wrote:

There can be, depending on the case etc.

Thats very theoretical and isnt how most cases work.

It can help but obviously that depends on how the fans are done.

The hard drives arent the main source of heat in most modern systems
even with that many drives. The main problem with that many drives is
that it makes it harder to have a free slot between each pair of drives
and when they are all mounted adjacent, you generally need a decent
airflow over the stack to keep the drives adequatey cool.

You wont get much of that if the drives are all
mounted adjacent in just one or two drive stacks.

It would generally be better to have a couple of fans blowing
directly onto the drive stacks, mounted at the front of the case,
essentially because the sides usually have the airflow obstructed
by the metal drive bay stack sides.

Try various configs with the hottest room temps it usually
sees and monitor the drive SMART temps with something
like Speedfan or Everest if they are ATA/SATA drives.

On 21 Dec 2006 15:10:39 -0800, "jg"
<juangarcia (AT) sacbeemail (DOT) com> wrote:

People demonstrate all the time that this "can" be done, but
similarly, most demonstrate it isn't necessary nor useful,
unless you are constantly getting inside the system to make
hardware changes.




With 8 drives I'd wonder if this is optimal. Even with a
large (120mm) fan, it isnt tall enough to push air through 8
drive slots, "maybe" if you had the drives stacked directly
on top of each other but this is to be avoided- drives
should have a minimum of 1cm between them with active
(pusher fan in the rack) airflow, even an entire inch, 2.5cm
if it's a passive intake. Having a fan push air through
some will not allow those not cooled by the fan to be
passively cooled with the 2.5cm of space instead, because it
is equalizing the pressure and diverts the passive airflow
away relative to what it would be if all racks had passive
intake.

The real question is, is the case suitable for the parts in
it? Some cases have more drive positions than they can
reasonably cool, while others have no trouble. Personally I
find the best configuration for cooling a large rack of
forward-mounted drives to be stacked 92mm fans, as they're
narrow enough to fit entirely within a drive rack framework,
no air escapes around the bay, it's ALL pushed through. For
best effect this also requires a fairly unrestrictive front
bezel intake area, but with this approach there is plenty of
margin should you want to put a large filter panel on the
front... which can work quite well since multiple front
92mm fans have enough power to positively pressurize the
chassis, so all air has to pass through the filter panel.


If your front fan has even close to sufficient flow volume
to cool the rack, it's doubtful you get significant
difference or benefit from the passive side grooves.

Why?

Top fans are best avoided, they reduce the airflow through
the power supply but more significantly, do so while the
other alternative (fan below the PSU on rear wall across
from the CPU and CPU-VRM power subcircuit) would help to
cool hotter areas more, and a more immediate movement of the
hot CPU 'sink exhaust out of the system instead of the PSU
intake being the closest to it, and running hotter as
result.

That doesn't mean top fans can't work, but are best seen as
complimentary to an already existing fan below the PSU, and
then only if your front intake fans move sufficient volume
that the rear exhaust fans aren't fighting against each
other to move the air.



Maybe, maybe not. When spun down a HDD doesn't create much,
and at idle, maybe 10W or so (varies per brand and model).
So that's 80W, not insignificant, but depending on the other
parts in the system or the average load put on it, might not
additively be that much higher (if even as high) as some mid
to high end systems, particularly those of overclockers or
gamers.

Is it a primary use system though, or a file/other server?
If a server, unless this is a demanding business environment
it's doubtful the rest of the system is generating much
heat, the CPU will idle down to the point where the
motherboard itself creates more, and then a carefully chosen
video card will consume under 10W... so it's entirely
possible you could be looking at a total heat load of under
160W average... or not, we don't have enough details to know
this, I was only speculating on what a system with 8 drives
is normally configured to do and the kind of load on it if
it's DIY instead of a ready made server kit.




Before presuming you need to change anything or leave side
panels off, check the temperatures while in it's expected
peak running state. It may be fine as-is, side panels on.
In particularly note the temps of hotter running drives or
those further from the fan. Note temp of video card if it's
not miserly, of chipset, CPU 'sink, and the motherboard VRM
capacitors... if they feel more than mildly warm they may
not have the lifespan you want... which becomes all the more
important if you're running a RAID off a motherboard
integrated controller instead of a more easily moved PCI
card, in that case you really don't want the board to die
and end up having to hunt down a replacement compatible with
your existing RAID sets... but again I'm just speculating,
we dont' have all the info.

If your fans are mounted on stamped-out-metal grills made
from the case walls, that alone is a significant impedance
to airflow and they ought to be cut out for better flow.

Not seeing the case and setup I can't guarantee it is going
to be adequately cooled as-is, but it is quite possible to
use # of fans you have and cool (at least) the parts
described thus far while leaving the side panels on. I
would leave them on unless you had the need mentioned above,
continual access to the inside for hardware changes.

"jg" posed a question:

What would move air across the HDs? If you're hot and sweaty,
would you just sit in the middle of the room and let convection cool
you, or would you want a fan moving air past you? Without those
case sides, the air entering the fans would just be air coming in the
sides of the case, and nothing would be driven past the HDs. What
you want is a "forced draft" caused by the fans forcing air through
the case - specifically between the HDs.

*TimDaniels*

"jg" <juangarcia (AT) sacbeemail (DOT) com> wrote

airflow. My everyday system has a Lian Li PC-60 series case with a 6 HDD
rack behind two 80mm variable speed fans and a top rack that holds two more
HDDs that I added another 80mm fan to cool. It used to have a top fan that I
took out because it disrupted the front to back airflow over my MB and
HS/Fan for the processor. I regularly run 5-8 HDDs for video work with at
least four drives in a couple of Raid-0 arrays that I render video from one
to the other for a bit of a speed increase. My ambient temps actually run
cooler with the sides on rather than off. While a side fan may help with the
processor cooling, it can disrupt airflow to other critical components. Do
some experimenting with your particular system and find out what works best
for you. I would try and stay away from removing the side panels just for
safety and keeping dust and debris buildup to a minimum. Keep enough space
between your HDDs to allow good airflow between them and you should be fine.
It doesn't take a lot of space between the HDDs if you have fans actively
blowing air over them. More space is needed if you passively cool them.

Ed

jg wrote:

S.M.A.R.T. hard drives can tell you their temperature. I believe that
HDD manufacturers' software or SiSoftware's Sandra can read this
information. http://www.download.com/3000-2086-10018691.html

Without knowing which case you have and how your drives are
mounted, I don't see how anyone can objectively answer. I like to
actively cool my hard drives-- I've felt how hot they can get, and
I'm certain that cooler is better.

Here is a Lian Li cooler that holds four drives and fits in 3 5-1/4" drive
bays (it comes in black, too):
http://www.newegg.com/Product/Produc...82E16841101035


Here are some other cooling related products I had bookmarked:
http://www.newegg.com/Product/Produc...82E16835185020
http://www.newegg.com/Product/Produc...82E16856999209
http://www.newegg.com/Product/Produc...82E16811999208
http://www.newegg.com/Product/Produc...82E16811999206

jg wrote:
Thanx to all who replied. Based on what I have read here, looks like
I'm better off with the covers on. I'm also considering the Liam-Li
cooler. But before I spend any $, I'm going to take some temp
readings. Also, because of the size of my case, no two HDD are
touching each other. So I might be OK with out the cooler. For a
picture of my setup... check out

www.acequality.net/temp/case.jpg

On 31 Dec 2006 00:19:41 -0800, "jg"
<juangarcia (AT) sacbeemail (DOT) com> wrote:



We can't see the front wall of the case inside the drive
rack, but it looks as though the air intake is in the bottom
of the front while ideally it would be mostly through that
drive rack... passively cooling a rack depends not only on
large openings in front of it, but also limiting intake
anywhere else. With intake though the rack, the top rear
fans will be helpful, as as well as moving some air past
that top rack mounted drive, though the drive on top of the
case looks like it could end up overheating too if there
isn't a large cutout area under it rather than just 4 strips
of metal pressed upwards for the mounting.

That's a lotta cabling you have there!