Temps down with side panel removed?

PhilC · Post by **PhilC** » Fri May 07, 2004 3:19 pm

Can anyone confirm that if your temps drop with the side panel removed that it means your intake airflow needs improvement. I think I have read this on a few threads, but can't recall for sure. My Sonata temps drop two to three degrees with the side panel off. I'm running two Evercool 120mm (optional 120mm for 2 Raptors). I also have done the lower bezel mod.

PhilC

PhilgB · Post by **PhilgB** » Fri May 07, 2004 3:40 pm

Mine just dropped 8degC by raising the case 1" off the ground

Was more restricted than I thought...

Bluefront · Post by **Bluefront** » Fri May 07, 2004 3:50 pm

IMHO.....it stands to reason if you improve airflow by removing the side panel, and your temps drop, you need better airflow (if you really need lower temps). Heh....

The real trick is to improve airflow without increasing the noise level.

dukla2000 · Post by **dukla2000** » Fri May 07, 2004 11:50 pm

PhilC wrote:Can anyone confirm that if your temps drop with the side panel removed that it means your intake airflow needs improvement. I think I have read this on a few threads, but can't recall for sure.

Certainly thats my opinion. It is a quick and easy way to get a baseline for what temps are possible if your CPU hs has pretty much free access to room/ambient temp air as compared to what it gets when cooped up inside the case.

PhilC wrote:My Sonata temps drop two to three degrees with the side panel off.

That is pretty good - dont panic. You know you have a problem when it is dropping 10C or more. It is 'normal' for a couple of degree drop because some of the heated air from the heatsink will recycle and this effect will be greater in a low airflow (=quieter) case. In fact if you are only dropping 2-3C I would think about reducing your airflow to gain quietness (to the point you have a 5-8C delta, and maybe even further if things are still stable and there is more quietness you can gain) rather than vice versa. In the extreme a 20C delta could be something you can justify to yourself because you know how much noise you have traded for that penalty. But of course the CPU temp is not the only temp to watch in the box: as you say you have a fan on your hdd, and if you have a high spec GPU you should watch that as well.

Tigr · Post by **Tigr** » Sat May 08, 2004 12:42 am

Yes, I think that Dukla is completely right. The air circulated by the CPU fan gets an easy way out of the box with the side panel open. Essentially, I think, without the side panel you get an independent cooling of each component. When the case is closed, all sorts of thermal dependencies between the components and the turbulence kick in. So, for the most cases, you will see a temperature drop of a couple degrees when you open the case.

Keep in mind that it may easily be the other way around for some components. The ones that are cooled passively through the airflow in a closed case become not cooled at all in an open case. For example, in a negative pressure case without front intake fan your HDDs are cooled by that intake air that is going in due to the negative pressure inside the case. Remove the side panel and this airflow stops. Your HDDs' temp will go up.

Anyway, when your temperatures jump a lot that means poor airflow. What Dukla suggests is to worsen the airflow a bit more in order to make it quieter. How much the temperatures should jump is very subjective and depends a lot on the actual case. I think that maybe 6-10 degrees is the "shadow area" between good and bad airflow.

PhilC · Post by **PhilC** » Sat May 08, 2004 9:28 am

Thanks for the input and advice. I think with this temp difference and the fact that I really can't do much more than I already have to improve the intake air flow (ie:lower front bezel mod) I'll just be happy with the status quo.
PhilC

muffled · Post by **muffled** » Tue May 11, 2004 8:28 am

I have exactly the same problem. I call it a problem because it bothers me that the noise goes up, because the psu sucks in more warm/hot air.
I openened a topic about this a couple of weeks ago, have you seen it?
http://forums.silentpcreview.com/viewto ... 3588#93588

PhilC · Post by **PhilC** » Tue May 11, 2004 10:02 am

Muffled: I just resd your thread, don't know how I missed it before my post. I have a Sonata case and I think you have a BQE which from what I've read are very similar. I think both these cases suffer from restricted intake air flow (ie:front bezel and horizonal drive cage configuration). I have done the recommended bezel mod on my Sonata and this did help.

IMHO, I think it needs more opening of the front bezel to solve this problem. I just havn't figures out how to do it yet without adding more noise escaping from the front. Both my 120mm Evercools run off the PSU fan only connectors and as temps rise so does fan speed and noise.

PhilC

PhilC · Post by **PhilC** » Tue May 11, 2004 10:04 am

Muffled: I just resd your thread, don't know how I missed it before my post. I have a Sonata case and I think you have a BQE which from what I've read are very similar. I think both these cases suffer from restricted intake air flow (ie:front bezel and horizonal drive cage configuration). I have done the recommended bezel mod on my Sonata and this did help.

IMHO, I think it needs more opening of the front bezel to solve this problem. I just havn't figures out how to do it yet without adding more noise escaping from the front. Both my 120mm Evercools run off the PSU fan only connectors and as temps rise so does fan speed and noise.

PhilC

muffled · Post by **muffled** » Tue May 11, 2004 12:20 pm

You're right, it always a compromise; less psu noise when you do that bezel mod, but more likely you will hear other noise, from your HD's or something.

Maybe that PSU mod is a nice idea, not a fan swap, but bending the intake grill, i'll give that a try I think.

bomba · Post by **bomba** » Tue May 11, 2004 1:34 pm

In my Sonata, While still using a M1BX modded stock Sonata PSU, I made some changes while observing results.

1. The addition of a front fan, resulted in a nominal increase in CPU & case temps as well as PSU fan RPM. Dramatically lowered HDD temps tho.

2. Blocking the "Antec" holes did not affect temps, but caused the PSU fan speed to increase.

3. I did a more extensive Bezel mod. Left the bottom alone but greatly opened the side intakes. Also, I removed all of the "slats" on the inner bezel. Strangely enough, at the time I did not attribute any improvements in temps or noise to the bezel mods. I also generally tape up the bottom intake as leaving it open tends to allow more (dusty) intake air into the case (bottom intake bypasses the filter).

My current L1A modded fortron is always quiet. Ultimately, I believe a PSU intake duct, as has been widely discussed, makes the most sense. On the Sonata, installation of a shelf under the PSU, extending forward should do the trick. This will encourage system heat to exit thru the rear case exhaust and will encourage the feeding of the PSU via cooler air thru the "Antec" holes.

PhilC · Post by **PhilC** » Wed May 12, 2004 9:40 am

Muffled; I have the newer 380s PSU with the SATA connector and the rear intake grate not the slots, so I think I'm ok on PSU rear intake.

Bomba: I think I might try the PSU intake duct idea. What would you use for the duct and how would you handle the PSU cables? Also, do you think it would be wise to remove one of the bay covers or would air from the side vent holes be enough(possible noise problem removing bay covers)?

PhilC

bomba · Post by **bomba** » Wed May 12, 2004 11:10 am

The TP380S fan controller seems to increase fan speed linearaly with any increase in measured temperature. Most of the heat measured by the PSU fan controller thermistor will be generated by the PSU itself. Thus, even if the PSU is pulled from the box and fed with cool intake air @room ambient temps, the PSU fan will still speed up (hopefully, to a lesser extent) as system loading and power consumption is increased. However, the Micke C. external PSU PC model is usefull for generation of baseline PSU fan speed and perceived noise level data under reproducable system loading conditions. If you don't mind having the PSU sitting on top of the PC case as an ultimate solution, this will also give the lowest PSU fan RPMs and PSU noise to system loading ratio. Your mission, should you decide to accept it, will be to come as close as possible to the baseline, while retaining the stock PSU mounting. For this, you (ideally) want a PSU fresh air duct.

Sonata PSU Fresh Air Duct:
Create a PSU duct by partitioning off the PSU/5.25" drive bay "compartment" from the motherboard "compartment", creating two independent air channels. Slide in an appropriate length piece of cardboard so that it rests on top of the upper motherboard tray flange and door side strut. Then pop the cover off an unused 5.25 bay, leave the drive door open, and see what improvement you get. If the prototype works out, replace the cardboard with something non-flammible.

Ok, if you're like me, a PSU duct is too much of a PITA; so lets explore an easier option. The CPU HSF sits directly below the PSU and below it the PCI & AGP slots, which may be loaded with heat generating cards. Alternately, you could use just a half-partition, from the front-bottom of the PSU, extending half the distance to the 5.25 bays. This should be enough to keep GPU & CPU heat from being sucked into the PSU and will ease routing of power cables. Finally, try it without the uncovered 5.25 bay, depending on the Antec holes for the PSU intake air path. As I stated prior, I'm satisfied at my current PC noise level and don't plan on doing any of this myself. If you do try any of the above, good luck, hope it works out & please post your findings.

PhilC · Post by **PhilC** » Thu May 13, 2004 9:15 am

Thanks bomba; I like your idea of a half partition duct considering the ease of routing the powe cables. I'll give it a try this weekend and post results. BTW, it looks like we have very similar rigs. What are your temps running? My case temps run 28c to 34c and cpu on average 3 degees higher at ambient 72F to 78F.

PhilC

bomba · Post by **bomba** » Thu May 13, 2004 12:14 pm

Ok, I guess I should say that I take all reported temps with a grain of salt. Doesn't make sense to me that my smaller HD in better air flow should be running hotter; felt temps are about the same. Also, without using the 8C Asus CPU temp fudge factor, case temps are typically reported higher than CPU temps.

Compared to yours, my temps are definitely higher, but I've got all the fans way cranked down. Under light load, reported CPU temp is typically mid to high 30's with case temperature reported a couple of degrees warmer. The hotter hard drive typically reports temps in the low to mid 30's.

We've had a recent heatwave here in the mid-atlantic and under light load without the house AC cranked up, I've seen reported CPU temps as high as 42C and the supposedly hotter (80G) drive reporting as high as 40C.

Oh and since I'm using an Asus P4P800 dlx; add 8C or so to the CPU readings. I've somewhat compromised temps for silence, but am comfortable with the temps. Normally, all I hear is a soft woosh from the PSU and HD fans. Case fan and CPU fan are essentially inaudible from more than a couple of feet away, even with the HD & PSU fans stopped. Speedfan is set to crank up the CPU fan from 30% to 50% at a reported temp of 47C (actual temp 47+8=55C?). Video encoding will bring the CPU fan speed up every time and CPU fan is audible @50%. Even w/ 2 instances of CPU burn running, 50% speed is sufficient to cool the stock clocked P4 2.8C. PSU fan speed does not seem to ever ramp.

mr_pickles · Post by **mr_pickles** » Fri May 14, 2004 6:34 am

My CPU load temps are on the scale of 8-10C lower with the side panel off. Is there some way to tell if I need more inflow or more outflow?

I've been experimenting with raising the RPM's on various fans and am having a hard time figuring it out. For the time being, I've bumped my exhaust fans (1 in back and 1 on top) up to 12V but it's too noisy for me. Even with them maxed out I'm only shaving off a degree or two if that. If I run my VGA silencer on the high setting, it seems to help out the CPU temps by another degree (must be the heat from the card rising up to the CPU).

I don't want to raise the RPM on my 7000-alcu as it's already the noisiest fan in my machine. Plus I don't think it will help as it cools it fine with the panel off so I feel it's more about either the air being fed to it or the lack of ability to get the hot air away from it.

Any suggestions that don't involve physical alteration of my case (I don't have the equipment, skill or inclination)?

bomba · Post by **bomba** » Fri May 14, 2004 10:29 am

Sounds like restricted intake to me. What is your system config, esp. CPU, CPU cooler, video card, case, fan configuration?

muffled · Post by **muffled** » Fri May 14, 2004 10:39 am

mr_pickles, what case have you got?
I noticed with my 3700BQE that it is important that the bottom intake is not restricted. It just moved my case a bit, so that the bottom can breath a bit better. This also helped to cool my HD better (but it is still too warm @45°C)

mr_pickles · Post by **mr_pickles** » Fri May 14, 2004 11:00 am

I have a Coolermaster 201C something or other. It's been renamed to the Praetorian.

http://www.coolermaster.com/index.php?L ... Praetorian

It has 2 fans in front, one in back and one up top. No bottom vent. All fans are 80mm (unfortunately).

I have a P4 3.0C and a 9800 pro, both of which produce a lot of heat. Maybe I should just accept that I'm going to have a hot machine. Knowing I can be 8 degrees cooler with the panel off does give me a baseline as far as how cool I can get it though and the differential between CPU and case temps does make me wonder.

The odd thing is that my case temp is relatively low and doesn't go down much with the panel off. I already re-applied AS5 (I mentioned this in some other thread) and shaved off a few degrees and I might get another degree or two over time as it burns in.

I'm thinking of experimenting with reversing fan directions. Also, the top fan is not mounted to the case directly but instead is in this mesh cage that hangs from the top. I'm going to try buffering it with some sorbothane to see if I can make the noise more tolerable so I can use higher RPM's on it.

mr_pickles · Post by **mr_pickles** » Fri May 14, 2004 11:17 am

My full specs if it helps:

Coolermaster 201C-something (now called Praetorian) case
Asus P4C800E-Deluxe board
P4C 3.0G with Zalman 7000-AlCu (with sorbothane mod that someone else here posted - works well!)
2 512M sticks of Kingston Hyperx 3500 DDR RAM
Sapphire Radeon 9800 Pro with Arctic Cooling VGA Silencer
Samsung 1614C drive (SATA, mounted in front of the intake fans)
Zalman ZM400A power supply
Soundblaster Audigy 2

Everything is at stock clock speeds.

Two intake fans in front (vertically aligned). One exhaust fan in back and one exhaust fan up top. All fan mounts are 80mm (unfortunately). All fans are Panalflo's L1A's except for the back exhaust which is some Coolermaster one that came with the case. All fans were undervolted with various fanmates or zalman multiconnectors (using 5V). Right now, I have one intake and both exhausts at or near 12V to see if I can lower my CPU temp but it doesn't seem worth the noise for the meager improvement.

Case temp is in the lower 30's (with or without the side panel).
HD temp is around 32C.
CPU temp under load is around lower to mid 50's. With side panel off, it drops down to about 44C.

As for why I'm focusing on load temps over idle is because I've started doing Folding@home (joined the SPCR team) recently so my CPU is almost never idle.

Any advice appreciated. Thanks.

mr_pickles · Post by **mr_pickles** » Mon May 17, 2004 6:39 am

Ok, I figured out my problem.

First off, I noticed that the little cage with the exhaust fan up top had a foam air filter. I removed it as I felt it was unnecessary for an exhaust fan. Sure, since it faces upwards, dust can settle in from the top when the machine is off but I'm willing to deal with that.

Secondy, I noticed that the foam filter at the front of my case in front of the intakes was clogged with dust. Since removing/replacing the filter in my case is a bit of a chore, I opted to just remove the filter entirely. It is much, much easier for me just to pop off a side panel and blow some compressed air around to clean it out than to clean the filter.

Now, my temps with the side panel off or on are within a degree or two of eachother. I was able to volt-down my fans again.

bomba · Post by **bomba** » Mon May 17, 2004 10:28 am

Glad you were able to track down the problems. Just remember now that you will be sucking all the dust that was stuck in your filters into the PC. Your Zalman 7000 will quite readily trap dust in the narrow gaps between the fins. You may want to periodically open up your case to check for dust buildup. I use compressed air to clean mine out when it gets nasty.

By the way, you may not need the blowhole fan. As an experiment, try unplugging it and taping up the hole to see how it affects temps & noise. Similarly, with only one hard drive, you may want to try only 1-intake fan. Don't block the intake of the disconnected fan however.

burcakb · Post by **burcakb** » Tue May 18, 2004 12:42 pm

PhilC, here's what I did with the PSU duct :

http://www.burcakbaskan.com/albums/PCMods/index.htm

Now, you'll notice 2 things: (a) air is coming in through the Antec holes, (b) I have a PSU fan right above the CPU so WTF?

The PSU is a Vantec Ion. The duct really does help as, even with the fan above the CPU, exhaust temps felt way down after the duct. I'm waiting for some Noiseblocker fans to do PSU modding, then, I'll change the PSU to a single fan one. I did cover up that lower fan but CPU temps went up. Nothing to worry about but why bother?

The duct material is some sort of plastic packaging material that looks like foam, doesn't burn or melt. I cut enough space in it to slip the cabling.

When I put in the new PSU I intend to replace the foam with duct tape too. Let's see how it'll work out.

Temps down with side panel removed?

Temps down with side panel removed?

Re: Temps down with side panel removed?