Is having your case open just as as effective as fans?

[duragezic]

So I was replying to a thread about my stupid noisy comp and why quiet the CPU fan if other fans are louder anyway. But then I stopped in the middle.. "hey stupid, so unplug the case fans". As far as I can tell the 7800GT fan is about the same as my 9800Pro fan. My 450W Fortron w/ noise killer MAY be a little more quiet than my 350W w/ noise killer, likely due to the 120mm fan instead of 80mm.

I always run the case off, so I unplugged the 60mm exhaust. That POS!! System noise dropped a LOT. Quite a few decibels I'd guess, which IIRC in the logarithmic scale means every drop of 10 means half as loud. Very noticeable. I guess I shouldn't thought of tha tlong ago cause its very cheap from this local crappy shop, and wanting to move to 120mm case fans (i.e. buying a new case), who've thought a 60mm would be loud as fvck, dummy! (don't know the rpms)

Then I unplugged my 80mm front intake fan. That one makes a less annoying sound, and much less quiet. I currently have it unplugged. I was gonna leave it plugged in, till I did combinations of the fans while monitoring the cpu temp and case temp under load (load being Prime 95 tests).

These are by no means scientific, but being in the winter it seems just as good to have the side panel off.

With the side panel off (how I've always ran it, cause I had an overclocked Barton with crappy cooling, now a Opty 146), and both case fans running: Prime 95 SmallFFT and LargeFFT brings load temps to up to 50° C. I don't believe I've seen 51 with this new HSF. Usually 48-49 though. When playing games and having speedfan chart the temps, they reached as high as 50°, but again, 48 and 49 are most common ehre. Case temps were 30° usually.

With the side panel off, and 60mm exhaust unplugged. Load temps (prime 95 only this time) 49° 95% of the time.

With the side panel off, and both case fans unplugged (much quieter, woot): load temps 48° most of the time, 49 a little.

I didn't try games with the fans off, but I prolly will later tonight. They dont seem to cause more heat than prime95 anyway. Case temps are around 31. I think those are fairly acceptable.

So as of now, I got lots of free quietness with no discernible loss in cooling power.

 

[DBSX]

I'm pretty sure this has been covered before, and the shorter, less-typing-involved answer is: Whatever works in an indivdual case works.

In general however, i think a clean, organized case with proper airflow and quiet fans is going to be better than an open case most of the time. Not to mention, the computer will be cleaner, and heaven help you if you have pets in the house.

When I was installing my new system recently, it was run for a few days without the side panel as I was frequently adding parts (the cost of ordering form different places is getting things at different times) and I found a difference of 1*C between running with no panel and running with it on. But I tried to make sure airflow was good, wires were tucked out of the way, and tried getting quiet fans. I think it all depends on the environment the computer is in, the organization of the case and the wiring, and correct fan choices/placement that makes or breaks cooling. My system is cool enough, and pretty near silent, without needing to risk my internals to the wrath of cat hair

\Dan

 

[Zim]

You are doing the right thing by experimenting.

What a case needs more than anything is good air flow. Air should generally flow from front bottom to back top... like a chimney. If you have good flow like this then taking the side off the case will disrupt it. The fact that you are getting better results with the side of your case removed tells me that you had poor air flow to begin with.

 

[gfngfgf]

Originally posted by: duragezicQuite a few decibels I'd guess, which IIRC in the logarithmic scale means every drop of 10 means half as loud.

A little OT: Half the decibels should be roughly half as loud (that's simplifying it quite a bit). The decibel scale is logarithmic, but so is human hearing.

If quietness is your main concern, I would think having the case cover closed would be best. It would at least muffle the sound of the CPU fan and most of the internal sounds. I think having good airflow in your case and keeping the side panel closed is a better idea than leaving it open, if only for dust concerns. If you can live with the extra cleaning, then I guess it's all good, though

 

[zagood]

The main difference I've found between side off and side on is that any passive cooling (i.e. northbridge) usually runs hotter, but the rest is close to the same or lower. Without a defined airflow through your case, passive heatsinks don't have the same amount of air flowing over them, so convection (in this case airflow to remove the heat emanating from the passive cooler) is almost non-existent.

If that's something to worry you, keep it in mind.

-z

 

[Fullmetal Chocobo]

I have the sides of my case open right now, the mobo side because I don't have the cooling mod done for the processors, and the PSU side because I'm still working on the window mod for that panel... I'm not worried about cooling on the PSU side, but the temps get hot on the CPUs if the cover is on. Hence the cooling / ducting mod I'm doing over there to get the fresh air on that side.

 

[robertk2012]

every increase in 10 decibles doubles the loudness. 70 decibles is about the same as a loud conversation or shouting, 80 is a vacuum cleaner and 110 is the same as a jet engine so you see doubling the decibles isnt the same as twice as loud.

Originally posted by: gfngfgf

Originally posted by: duragezicQuite a few decibels I'd guess, which IIRC in the logarithmic scale means every drop of 10 means half as loud.

A little OT: Half the decibels should be roughly half as loud (that's simplifying it quite a bit). The decibel scale is logarithmic, but so is human hearing.

If quietness is your main concern, I would think having the case cover closed would be best. It would at least muffle the sound of the CPU fan and most of the internal sounds. I think having good airflow in your case and keeping the side panel closed is a better idea than leaving it open, if only for dust concerns. If you can live with the extra cleaning, then I guess it's all good, though

 

[gfngfgf]

I did some reading and you and duragezic are correct and I am wrong. I guess I didn't really retain as much knowledge from my acoustics class in college as I thought I did

Originally posted by: robertk2012
every increase in 10 decibles doubles the loudness. 70 decibles is about the same as a loud conversation or shouting, 80 is a vacuum cleaner and 110 is the same as a jet engine so you see doubling the decibles isnt the same as twice as loud.

Originally posted by: gfngfgf

Originally posted by: duragezicQuite a few decibels I'd guess, which IIRC in the logarithmic scale means every drop of 10 means half as loud.

A little OT: Half the decibels should be roughly half as loud (that's simplifying it quite a bit). The decibel scale is logarithmic, but so is human hearing.

If quietness is your main concern, I would think having the case cover closed would be best. It would at least muffle the sound of the CPU fan and most of the internal sounds. I think having good airflow in your case and keeping the side panel closed is a better idea than leaving it open, if only for dust concerns. If you can live with the extra cleaning, then I guess it's all good, though

 

[the Chase]

Or just forget the case and run your mobo laid open on the table with no fans at all!!