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My Noisy System

Posted: Sat Nov 08, 2003 5:01 pm
by canthearyou
With all the great quiet systems, I thought I would post some photos of my noisy system. The question is whether to try quieting this one until I start building a new system.

A500

Posted: Sat Nov 08, 2003 6:02 pm
by MikeC
When I turn the PC off, I can reduce the TV volume by half.
:lol: :lol:

You're right about this one. Where to begin?! Not that it can't be done, but there's just a LOT to be done. Would be easier to build a new one with better options to start with.

Posted: Sat Nov 08, 2003 6:25 pm
by canthearyou
Yeah, the case was not really designed with quiet or cool in mind for the class of CPUs that came out since then. Very nice though. I will have to replace it with something, but have to think about spending $ that might go into a new system.

A sort of crazy idea. I thought about moving the HD up to the top bay with the I-storm and ducting it back to the front vent of the PSU.

I'd rather have the HD down at the bottom in front of the case fan.

The case fan contributes to cooling the MB a degree or two, but does nothing for the CPU.

The I-storm has got to go, I keep bumping into it and it has developed a whine. I like the Zalman heat pipe, but that is expensive for a temporary solution.

Oh, I forgot, the Northbridge fan is kicking up a racket.

Steve

Posted: Fri Nov 28, 2003 3:35 pm
by canthearyou
There is about a 65mm square area to place a heat sink. I would say 55mm HxWXh is reasonable.

I looked at the airflow around the Orb with a strip of paper. It appears to flow out of the bottom and into the top fins. I'm not sure how easy it would be to remove the fan to place a duct from the PSU into the Orb. The airflow sucking from the PSU does not appear to be enough. And it seems to me that the duct might block the airflow across the top fins, which appear to do most of the cooling. I do like the ducted fanless Zalman seen on this board, but I have my doubts about converting this one.

Posted: Tue Dec 02, 2003 5:39 pm
by canthearyou
Taking all the information here in forums into consideration I was able to look at my case in a different light. I figured that if I ducted the HSF into the PSU intake, which is very close to it, I could vent the major heat producer quicker and by boxing in the PSU/CPU area bounded by the video card (as I've seen here in the forums) I could get the heat out of the box quicker. I could keep the case heat from affecting the PSU and CPU, keeping the PSU fan speed down. My case has a spot for a front case fan with some vents in the bezel and in the rear above the cards is a long vent. I thought that if I isolate the "hotbox" and keep the case fan blowing inward, that the flow would go over the cards and out the rear vent. It has an almost direct path. I also think that this arrangement cuts down on turbulence and competition between the HSF and PSU intake, which are 20mm apart.

I made a made a duct enclosure. Paper encloses the area between the HSF and PSU intake cutting the case off from the PSU. The case is vented only by the flow from the front case fan exiting the rear vents above the cards. The MB temp has been lower than usual at 31C, usually 36C. So the PSU does not get the heat load from the case.

All the heat load of the HSF is vented through the PSU, which is the most direct path.

Immediately the sound of the HSF was reduced by about 90% with the flutter and chuffing inaudible outside the case, just a lower whirr. The high frequency sound from the HSF was gone. The PSU now was predominant. I was surprised that an enclosure made only of lightweight laser paper could do.

The I-Storm was not powered, but still in the bay. This does affect temps of the HD slightly, lowering from 34C to 31C if I take the hood off. Closing this off completely would raise the HD temp.

I monitored the flow out of the PSU with a remote thermometer. It stayed at 31C steady.

HD temps were much lower until the case heated up a bit after 30mins, about 36C, but was in the high 20s for a long time.

MB was very steady at 31C.

CPU was lower than usual then rose to 47-48 under light browsing load.

PSU fan was much lower than usual for much longer, rising slowly to 2200, which I think is less than the usual top rpm. It was going back and forth between 1900 and 2300. It was 1700 for a long time, very unusual without the duct.

The PSU exhaust feels warmer than normal, but I did not take a reading before adding the duct.

up to 32.9C after 30min, 1hr

HD holding at 36C after 1hr

Ambient room temp measured on top of the case front 27C (winter).

the MB temp is lower with the duct from 47-49 depending on the ambient temp. Now it is topping out at 48C when it normally would top out at 47-48C all day.

although the CPU fan is not temp controlled, it does vary with heat, from 5800 to 6800 normally, but with the duct the speed is staying at 5800

Conclusion is that more fans is not the answer, ducting reduced fan speed and temps from the highest, although probably did raise the CPU temp a bit. Also, the vent holes down the side of this case likely contribute nothing but a sound path and unhelpful flows. It does show that dividing the case into differing heat loads helps.

I'm certain this case does not have sufficient airflow because when the cover is off temps dropped by one.

Some pictures.
http://www.city-gallery.com/knoblock/a500duct-1.jpg
http://www.city-gallery.com/knoblock/a500duct-2.jpg

Sorry if this is rambling, I've just done the experiment, Opera does not seem to like BBCode buttons, can't seem to link the pics, have a cold.

Posted: Tue Dec 02, 2003 7:22 pm
by Shadowknight
Sounds interesting, just one thing... your links don't work. Check the file names, maybe?

Posted: Wed Dec 03, 2003 1:56 am
by ruprag

Posted: Wed Dec 03, 2003 1:59 am
by Zyzzyx
I've got a modest upgrade for ya from plain ol' notebook paper:


Cereal box.


Far stiffer, yet still nice and easy to work with. And you were probably gonna toss it in the recycle bin anyway.

Posted: Wed Dec 03, 2003 11:32 am
by canthearyou
Thanks ruprag, getting over my cold today so hopefully I will be more coherent.

I may use a Priority Mail box for the cardboard to build the actual duct.

The CPU fan, to be more specific, has a kind of wing flapping sound mixed in with the whirring. I don't hear that with the duct.

It is fascinating how decoupled the various heat producing parts parts of the computer are. I've watched the PSU (fan speed), MB, CPU and HDD temps change independently of each other while making changes to various fans. A good example is that the front case fan contributes nothing to the CPU temp as far as I can see. That's what led me to think it would better be employed to just cool the MB and flow out the back.

This is America. We don't need no stinkin' recycle bin. ;-)

Posted: Fri Dec 05, 2003 6:17 am
by pangit
Sounds interesting, icanthearyou, as although it's difficult to see from your photos it sounds like you're trying to do something that I want to try. I got the idea from Spydercat but I haven't tried it yet. I will over Christmas if I have time. :wink:

I want to direct all the air from the CPU into the PSU, so it doesn't recirculate and heat up the other components in the case.

Dunno if it will work though, I'll let you know if I try it......

Posted: Fri Dec 05, 2003 7:53 am
by canthearyou
I was inspired by
this cardboad duct and am interested in the other duct with the fan reversed. The problem is I cannot just take the fan off the top of the heat sink to flip it. The fan sits in the middle of the heat sink.

I'm seeing a bit higher temps on the CPU with the duct, but not more than somtimes without it and it is quieter. The PSU fan does run about the same rpm after warm up. That is loudest. It is quiet at about 1400-1700rpm and runs about 2400rpm, goes to 5000rpm under gaming load---does not get above 50C CPU even after an hour. The MB is lower at 32C with this arrangement (compared to previous figures
HDD 29C MB 36C CPU 49C with no duct or case fan and i-storm running on a warm day). The case fan is doing a good job cooling MB. I think the i-storm, although keeping the HD at 28-29C was dumping most of the heat from the HD into the PSU and MB, so it was positive to remove that. I have the bay closed now. I plan to move the HD down to in front of the case fan but there is no lower drive cage.

My case was particularly suited to separating heat loads because of the front case fan and the vents above the cards.


another duct

Good Luck

Posted: Fri Dec 05, 2003 8:00 am
by canthearyou
Same thread I see.

Also: with the case open my temps are much lower, MB 29C, CPU 45 and PSU fan 1400-1800 with the duct about the same, MB30C, CPU47 but the fan goes up a bit higher. This shows it's not the duct that is raising the temps, but the load from the case. I might improve this by moving more air through the case.

ideas

put a small fan in the upper right corner inside the duct to vent some heat out the back

enlarge front vent/add 120mm case fan with duct in front

PSU w/120mm fan to move more air out of the duct