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Case Air Flow Management

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June 26, 2002 11:05:24 AM

Hello.

My system is:
AMD Athlon 1400
Globalwin WBK-68 (4400 rpm) & ASII
MSI KT266 Pro2 RU (KT266a)
512 DDR PC2100 (two sticks)
Leadtek Geforce 3
2 x WD400BB 7200 rpm in Raid 0
DVD Pioneer 106S
Teac R56S CDR SCSI
Adaptec PCI SCSI Card
Compex 10/100 PCI Lan Card
Sounblaster Live
1 intake fan (low-front)
2 outtake fans (high-back)
Generic 30-euro full tower case
Herolchi 350W PSU (one fan blowing out)

The CPU temps are 60/65 and the case are 45/49 (idle/full). I have 3 ata flat cables and one flat SCSI in the case going through a 5x5 cm gap that seperates the lower (mobo area) and the upper (CDs and PSU) areas. Two of the ATA cables go all way to the bottom of the case to the RAID slots and i think they block the intake current.

1) Will round ATA cables help me?
2)I am thinking of adding HDD fans and the PCI fan card that goes below the VGA (which i think is generating too much heat).
3) Is a PSU with intake and outtake fans better?
4) Will covering all holes in the sides of the case improve the air flow?
5)Is the generic case increasing my temps? Will i see a difference if i buy a known brand case?
6) How much of an impovement should i expect if i do all of the above?

Thank you for your help

Naval aircaft don't land, they crash under controlled conditions...
June 26, 2002 5:26:21 PM

In my (limited) experience, the intake fan is very important. Be sure it has a clear opening. I added a 60mm fan in the side of my case, dropped case temp about 4C. then i removed the front intake 80mm fan (mostly blocked by the bezel). no change. clear intake is the key.

My system specs are almost exactly the same.
XP 1600+ at 1.4 (if you've got a thunderbird at same speed it may run a bit hotter)
Thermaltake Volcano 6Cu (5k rpm)
Gigabyte 7vtxe (kt266a)
Leadtek Geforce3 ti200
60mm intake (side), 80mm exhaust, psu exhaust

Watch out for that leadtek geforce3. The fan on mine has stopped working a few times (7 months old?), and it has a slight grinding noise to it (even after cleaning it). As you can imagine, its not good for the case temps when that fan stops. Measuring temps at the edge of the heatsink (top of the card) it was at 41C. yikes. my new intake fan blows right on top of it.

Your list:
1) round cables won't do much if you're not getting enough air in to go around them

2) your hard drives shouldn't be making enough heat to need special cooling, unless you mean putting intake fans in your 5 1/4 drive bays. That air will help cool your cpu a bit, but not the video card. the air will most likely be sucked straight through the top of the case and not circulate. Good way to test this: remove the front bezel (provided you've cut out all the metal tabs in the drive bays).

3) Stick your hand on the back of the PSU. does it really flow that much air? i think your 2 exhaust fans blow a lot more air than any PSU would. focus on better intake.

4) This would probably hurt your temps, especially since your case is most likely starved for any intake air it can get (3 exhausts and only one, probably blocked, intake). Hold a sheet of paper up to the side vents. It'll probably get sucked right up to it.

5) probably not. as long as you can get a nice flow of cool air through the case it'll be fine.

6) not much.

Sounds like you have great exhaust, just need some intake to balance it out. I really recommend a side intake. cut a hole and move one of your exhaust fans down there. ask if you need help with this. my 60mm fan was the first mod i did, and i'll do it differently next time =)

here's some of my temps for comparison:
idle (well, typing this)
25 / 33 / 48 : ambient / case / cpu
idle with the front bezel removed:
25 / 34 / 49 : yes, it actually hurts temps, this was after about 2 minutes
June 26, 2002 6:04:28 PM

"1) Will round ATA cables help me?"

Yes. There will be less resistance to to the airflow through the case.

"2)I am thinking of adding HDD fans and the PCI fan card that goes below the VGA (which i think is generating too much heat)."

That will help the components but not your overall situation. Don't get me wrong, theye will help but you have a internal heat disipation problem. They will help in airflow into the case but they would only help a little overall. If used in conjunction with a better layout they would be much more efficient.

"3) Is a PSU with intake and outtake fans better?"

Most likely yes based on mechanics. The PSU will have better airflow itself, however that does not mean the case will.

"4) Will covering all holes in the sides of the case improve the air flow? "

It would help create a better seal and thus a better positive or negative pressure inside the case. It could actually decrease the overall airflow. It depends on the if your case is drawing in as much air as it is pushing out. (If you want me to go into greater detail I will.) See below...

"5)Is the generic case increasing my temps? Will i see a difference if i buy a known brand case?"

Not necessarily. So cases are designed better than others. Some are made from better heat transferant materials than others. Modifing your case would probably be more cost effective than purchasing a new case and maxing it out.

"6) How much of an impovement should i expect if i do all of the above?"

You have a lot of heat sources in your case. T-Bird 1400, GeForce 3 card, SCSI card, etc. However you are trying to force out more air than your case is taking in. If you covered the holes you would get even worse results. (Like I said, if you want me to go into detail why, I will.) You need a more balance air intake and exaust. If you did all of the above you might get better and you might even get worse results. I know that this sound way to generic, but I will have to get more in depth in this discussion and I don't have the time right now. Respond to this and I will respond sometime tomorrow. I just don't have the time today.

(I am going in to see the Doctor for the results of the sonogram. My wife and I are having a baby. BooYah!)

<b>"Sometimes you can't hear me because I'm talking in parenthesis" - Steven Wright</b> :lol: 
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June 26, 2002 9:19:38 PM

Thank you both for your replies. I did some tests this afternoon and the results are:

If i have my case open the case temp rises about 2C. If i unplug the intake fan the temp rise about 4C, so the intake works well. I also covered the side holes (they didnt "suck" air, the paper just fell down) but nothing changed.

I have added a second intake fan to the side of the case (it is in the lower front of the side oppposite the motherboard). The temps are the same but i will try putting the same fan tomorrow to the lower back so that it blows directly above the SCSI - VGA cards and see if this improve things.

I didn't know that the SCSI card is generating much heat, maybe its time to replace the 6x write CDR to a 40x write ide CDRW (and get rid of the SCSI cable and card). One more thought is to rearrange the HDD drives and put them to the top of the case, even above the DVD and CDR so that their heat wont affect the lower part which is very crowded. I will also try getting new round ide cables to replace the flat ones and see if this improves the airflow

I am coming to the conclusion that the high case temps are from: 1) my high ambient temp ( i dont have an a/c unit and the room gets very hot) 2)the vga is generating way to much heat, its temps are 59c chip and 63c board (these are idle temps from the self-monitoring utility) and 3) the 1.4 tbird (i am also planning on replacing it with a XP1600+ or a XP1800+ and a new HSF)

Palp



Naval aircaft don't land, they crash under controlled conditions...
Anonymous
a b K Overclocking
June 27, 2002 1:52:26 AM

your case temps are way too high. this assumes that your room temps aren't that high. Case Temps in well ventilated systems usually only a couple degrees higher than ambient room temp if that.

Too high a case temp implies poor air throughput.

Sounds to me like you have a big enough number of fans, but maybe need to do something to improve circulation. One thing I did that has made my fans drastically more efficient, was to grind out 80mm holes where the fans mount. I figured all that swiss cheesed metal was getting in the way. Unfortunately I don't have before and after data since I just did it at buildup time. my fans are deffinitely creating more air pressure (in front of them of course)now though.
June 27, 2002 12:02:16 PM

Unfortunately i dont have the tools necessary to cut the case so i am stuck with what the case offers me.

I put the side fan over the lower back part but the SCSI cable partially blocks the fan. The case temp went 2C down but the CPU temp increased by 2C, so that's not very good.

Another thing that i remember is that when i changed motherboard the case temps increased by 8-10C (the internal temp reader might me off - should i use another program?), also the case temp increased when i replaced my VGA (from a Radeon 32SDR to a Leadtek Geforce3) and when i installed the second HDD.

Tomorrow i will buy the new CDRW and round cables and i will post the results...

Naval aircaft don't land, they crash under controlled conditions...
June 27, 2002 5:22:26 PM

Did you use the paper by the fron intake fan or on the holes?

The holes on the side wouldn't have enough negative pressure to draw the paper in.

As for temperatures, what is room temp for you and what is the case at? What is the exhaust air temp?

Just let me get this straight...

1. You open the case and the temps go up 2C.

That would be because you are drawing in air using the rear fans and the excess heat is not being forced out. Opening the side will negate airflow. No airflow, no collision of molecules against components, increased latent energy, increase in heat.

2. Intake fan is operational.

3. Disconnecting the intake fan caused temps to increase.

That is due to a decrease in the airflow through the case. See #1.

4. "I didn't know that the SCSI card is generating much heat, maybe its time to replace the 6x write CDR to a 40x write ide CDRW (and get rid of the SCSI cable and card)."

Of course it is not a lot of heat but replacing the SCSI card would eliminate one heat source and should decrease temps.

5. "One more thought is to rearrange the HDD drives and put them to the top of the case, even above the DVD and CDR so that their heat wont affect the lower part which is very crowded."


Actually that could help but the heat will build up and be transfered eventually to the rest of the case.

"I am coming to the conclusion that the high case temps are from: 1) my high ambient temp ( i dont have an a/c unit and the room gets very hot) 2)the vga is generating way to much heat, its temps are 59c chip and 63c board (these are idle temps from the self-monitoring utility) and 3) the 1.4 tbird (i am also planning on replacing it with a XP1600+ or a XP1800+ and a new HSF)"

I'll give you number 1, big time. You are correct with the GPU and the T-Bird statements.

You need a better overall cooling soulution.

a) What are your ambient temperatures?

b) What fans do you have? (Make and model will answer the spec questions.)

c) What do you want to spend to decrease these temps?

d) You mentioned that you did not have tools. What do you have or are willing to purchase or borrow to modify your case?

e) I'll come up with more later...

<b>"Sometimes you can't hear me because I'm talking in parenthesis" - Steven Wright</b> :lol: 
June 27, 2002 10:04:05 PM

"Did you use the paper by the fron intake fan or on the holes?"

I used it on the side holes. The front side of the case is solid, it doesnt have an opening for the intake fan. The air that the fan sucks in comes from the lower front corner (the corner between the front and bottom of the case)

"As for temperatures, what is room temp for you and what is the case at? What is the exhaust air temp?"

I dont have a thermometer in the house (lol!). I will buy one tomorrow and give you the temps. The room though is hot, i estimate around 28C with the lights on, pc on etc. More acurate readings tomorrow.


Today i had some free time and so i went to the local computer shop. I got the CD-R (a Teac 40w-12rw-48r) and two ide round cables. I rearranged the HDDs so the IDE devises in my case are from top to bottom: HDD#1 - HDD#2 - DVD - CDR. The SCSI cable and card are out (i closed the pci-exit hole with a "metallic strip" that screws like a pci card). I also rearranged the PSU cables a little bit. The results are a 4C drop, not bad but not impressive.
I tried the side intake fan in two different positions but the temps were increasing or stayed the same, perhaps it is disturbing the air flow more than bring cool air in.


"a) What are your ambient temperatures?"

Dont know, will know tomorrow when i get the thermometer"

"b) What fans do you have? (Make and model will answer the spec questions.)"

CPU HSF: Globalwin WBK68 (4400rpm)
Intake Fan: Evercool 80mm EC80255M12S 12V 0,14A 1,68W (dont know the rpm,it connects directly to the PSU)
Outtake Fan #1: Cooltium 80mm MW825M12B 12V 0,12A (2.900 rpm)
Outtake Fan #2: Spire 80mm FD08025 12V 0,15A (2350 rpm)

I think that the two outtake fans are generic crap but a known-brand fan wont make a big difference to justify the extra money (15 Euro perhaps each)


"c) What do you want to spend to decrease these temps?"


Not much. I gave today 160 Euros to buy the stuff i wrote above, perhaps another 50 Euro but only for a 4-5C drop. (1 Euro = 1 USD)


"d) You mentioned that you did not have tools. What do you have or are willing to purchase or borrow to modify your case?"


Purchase no, they are too expensive and i will probably only use them once in the case, so its a waste of money. Borrow yes, i am not good in these kind of modifications but i can try. What tools do i need and what should i cut/mod?


"e) I'll come up with more later..."

ok


Thank you very much for your help!

Palp

Naval aircaft don't land, they crash under controlled conditions...
Anonymous
a b K Overclocking
June 28, 2002 6:02:57 AM

I think 4 degrees is amazing considering what you did.

I'm getting this much from what has transpired here: you have good exhaust (probably not the issue), and bad intake (most likely the issue).

To fix it beg borrow or steal whatever your mind can concieve carving a hole with and just do it! Bottom front, mount a fan as an intake, filter if you want, and watch case temps drop like crazy.

Just keep in mind that a mix of flying metal fragments and expensive electronics is not good for your pocketbook.

Make it so.
June 28, 2002 7:42:01 PM

The <A HREF="http://www.spire.nl/asp/hdd.asp?ProdID=22" target="_new">Spire blower</A> is not a really good fan. Most blowers for a matter of fact are not that good. They create more noise than CFM. The fan is a 4500RPM, 25.6 dBA, 16 CFM, blower. You are not moving much air out through here.

The MW825M12B throws me for a loop. It is most likely the T&T (TOP AND TECH(CS)) MW-825M12B. 1CoolPC used to sell these but has since switched to the <A HREF="http://www.sunon.com.tw/product/traditional/t8025.htm" target="_new">Sunon KD1208PTB2</A> which is a 80mm^2 x 25mm, 2900RPM, 32 dBA, 92.5 gram fan. However it could be a Globalwin fan as well. Their <A HREF="http://www.globalwin.com.tw/product/other.html####" target="_new">80mm^2 x 25mm</A>. There is a <A HREF="http://www.infomaniak.it/newsite/viewProdotto.asp?ID_PR..." target="_new">fan with a air channeling unit on this website</A>.

I am not sure... Do you have a link or is the case really old? 4-6 years or more?

As for that GlobalWin WBK68, That is not a great cooler. It is okay but will a high ambient temp this cooler is terrible, sorry to say. It has a <A HREF="http://www4.tomshardware.com/cpu/01q2/010521/cooler-32...." target="_new">0.45 C/W ratio</A>. An <A HREF="http://www.micforg.co.jp/c_pal8045e.html" target="_new">Alpha 8045T with a modest Sunon, Delta, Papst, Panisonic, etc. fan</A> can beat that hands down in terms of cooling and dBA's. (0.26~0.28 C/W and 27~40 dBA) The GlobalWin WBK68's fan gives off 50 dBA. So you could improve your CPU cooling greatly here.

"Intake Fan: Evercool 80mm EC80255M12S 12V 0,14A 1,68W (dont know the rpm,it connects directly to the PSU)"

I don't quite follow you here. Are you saying that this fan is attached to the PSU and is intaking air into the PSU from inside the case? If so that is not really an intake fan. Or did you reverse the fans direction to blow from the PSU into the case? (I doubt it.)


For tools to cut metal, a Dremel hand tool is very useful. A drill and a hacksaw or recipricating saw with a hacksaw blade and or tin snips will cut nice holes in your case. If you screw up a little a grill can cover some of your mistakes.

If you have the make and model of the case I can scetch up some ideas on how to attack this project.

Maybe a 120mm fan over the AGP and PCI/ISA slots that is attached to the side panel...

Bigger hole in the fron pannel...

Blow-hole out the top...

There are many things you can do. Specs will help for the layout of the cooling setup.

Back to you...

<b>"Sometimes you can't hear me because I'm talking in parenthesis" - Steven Wright</b> :lol: 
June 28, 2002 9:48:57 PM

Hmmm i must have read the codes for the fans wrong.

The spire fan is actually <A HREF="http://www.spire.nl/asp/hdd.asp?ProdID=24" target="_new">this one</A>. It's a 28dba, 28,80CFM fan.

The stats for the evercool system fans are in <A HREF="http://www.evercool.com.tw/products/fan_8025.htm" target="_new">this</A> page. I dont find an exact match for the model i have in my case(EC80255M12S, 0.14A, 12V), maybe it's discontinued, but judging from the amps it must be between the 0.16A and 0.11A in the list, blowing around 35CFM at 26-27 dba. The power connector of the fan connects to a PSU cable that gives power to the HDD, CDs etc (like some of the 7000 rpm CPU fans). It is an system intake fan not a PSU intake.

The <A HREF="http://www.globalwin.com.tw/new-product/Wbk68.html" target="_new">Globalwin WBK-68</A> is a 4800±15 % RPM, 23.7±15 % CFM and 36.5±2 dBA. Mine is running at 4350 rpm right now so the cmf must be 21.5 and the dba 33.

I cannot find a link for the Cooltium fan but at 2900rmp it must give around 28-30 CFM and 26-28dba.

Overall my pc is very quiet. I had a fop38 with a 7k rpm delta fan when i first build it and i couldn't stand the noise. My main concern is to have a quiet and stable pc even if i cant overclock it (although in the winter months a had it at 1500MHz - 10x150 at 1.75vcore running stable). My next HSF to go with the AXP2200+ will probably be an all-copper globalwin 4500rpm fan (CAK-II 68 or CBK-68).

I dont have a link that shows the case (its a john doe generic case) but i understand your instructions. I will try to find the saw and other stuff and try to cut some holes (the font and side ones i think will help alot)

Sorry for not providing the links for the fans in my previous post.

Thank you for your help
Palp

Naval aircaft don't land, they crash under controlled conditions...
June 30, 2002 8:31:51 PM

"Overall my pc is very quiet."

Based on my experience, this is the side effect of an inefficient cooling system. A good cooling system is usually pretty loud, or at least moderately loud unfortunately. If it's this quiet you can probably bet that your case fans aren't moving much air at all.

Altogether, your fans should be making some noticeable noise if they're going to be doing their job. Otherwise if you truly want a silent PC you have to ditch that GF3, SCSI, and CDR/RW (there's no such thing as a cool silent and powerful PC despite what fan manufacturers want you to believe). Your generic case doesn't sound too good actually. I had a case like yours once. It had 1 80mm slot for an intake fan.. actually it was more like a prison. Between a sandwich of plastic, a metal sheet, and a strange plastic grill, in the end my 20CFM fan ended up being only about 5CFM.

Overall you should expect your system noise to hover around 35-40dB, noisy but tolerable and not noticeable when using your computer for extended periods of time.

It sounds like what you need is just better intake. If case mods fail you, there are plenty of alum cases that can be had for as little as $60.

This little cathode light of mine, I'm gonna let it shine!
July 1, 2002 3:52:39 PM

So what would you like to attemp?

You can cool the CPU better which I described above.

You should be able to cut a bigger hole in the front of the cas and you could use a 92mm or 120mm fan with high CFM and low dBA levels.

You can change the fans in the back to get better results.

You can cut a hole in the side pannel for a 92mm or 120mm fan to cool the AGP, PCI, and ISA (if you have any) slots.

All of these are not that difficult to do.

<b>"Sometimes you can't hear me because I'm talking in parenthesis" - Steven Wright</b> :lol: 
Anonymous
a b K Overclocking
July 1, 2002 5:26:39 PM

(Hip Hip Hurray! Life is coming to be born.)


<i>if you know you don't know, the way could be more easy ...</i>
July 1, 2002 5:50:27 PM

???

<b>"Sometimes you can't hear me because I'm talking in parenthesis" - Steven Wright</b> :lol: 
July 1, 2002 8:16:47 PM

I think his wife's having a baby.

This little cathode light of mine, I'm gonna let it shine!
July 2, 2002 2:19:58 PM

Probably i will go with the side hole over the PCI slots as it is easier to do.

Thank you very much for your help

Palp

Naval aircaft don't land, they crash under controlled conditions...
July 2, 2002 2:48:32 PM

No problem.

Do you have the fan picked out?

If you are going to use a 120mm fan you can use a CD for diameter. It is the perfect size.

<b>"Sometimes you can't hear me because I'm talking in parenthesis" - Steven Wright</b> :lol: 
July 2, 2002 5:15:40 PM

I will try to find the best CFM/dba fan so the bigger the better. Also i opened the case again today and i saw that i can easily cut the front plastic so that it wont block the intake fan. All i need now is to find the saw.... :) 

Naval aircaft don't land, they crash under controlled conditions...
July 3, 2002 4:59:54 AM

I think if you want to replace the case with one that got some nice cooling options, you should take a look at the Antec SX1030 or SX1040. They got 4 spaces for case fans (2 front 2 rear), after some clearing out of the factory grilles it will gives great flow to keep your setup cool. They're also pretty large to make it not so crowded when you got lots of toys to fill a case. :) 

If I would have to buy a case right now I would get the SX1030 and 4x80mm case fans with the temperature sensors so they run at the best speed according to temperatures. I still like my case enough not to replace it right now, but you never know whit me. :D 

<font color=red>Got a silent setup, now I can hear myself thinking.... great silence</font color=red>
!