Air Flow Problem? - Tilted Forum Project Discussion Community

wombatman · 05-27-2005, 08:08 PM

I've got a Thermaltake Xaser III case. I just replaced some of the fans (the front 2 80mm, the back 2 80mm, and the top 80mm) with Sunon Ultra fans (~50CFM at ~40dBa) to try and lower the case temps and hopefully the processor temp as well (by having more, cooler air moving through). Oddly enough, though, the case temps have actually gone up by about 3 or 4 degrees (under load). The processor temp is about the same.

Summary:
7 case fans total, all 80mm, ~21CFM, ~28dBa
Replaced the 5 mentioned above with ~50CFM, ~40dBa Sunons
Case temp went up

What would lead to this?

wombatman · 05-27-2005, 09:25 PM

Alright, so remembering to plug in the top blowhole helps a lot. Dropped the case temp about 3 degrees. Still seeing higher case temps than before however.

cyrnel · 05-27-2005, 10:39 PM

The fans are pointing the correct direction, no? If you can't remember which pointed where, try both front and lower rear for intake and the rest (plus p/s) for exhaust. More intake (positive case pressure) makes for a cleaner case.

I thought that case had a duct for processor air intake? Might have been another version of the side panel. If not, try ducting an intake fan to a processor shroud. Cobble something from cereal box cardboard if you have to just to see if it makes enough difference to get serious.

Be careful about cable placement. Get them out of the way, without creating turbulence or interfering with important airstreams.

Edit: Another thing - are you sure the new fans are really moving more air? Compare an old and new. Make sure the new intake fans don't have thermal sensors or they'll never come up to speed.

wombatman · 05-28-2005, 09:06 AM

The front and side fans are doing intake, the top and back are doing exhaust. I'll see about reversing the lower back fan and seeing what happens. The side panel on this case doesn't have a duct, but it is lined up over the processor, and the 120mm fan I have on the XP-120 heatsink is a Panaflo moving 115CFM, and the temperatures on that are satisfactory (no higher than about 57 degrees C or so). The cable placement is likely a cause of my trouble, as they are all over the place. I'm working currently on improving that.

The new fans should be moving more air and are not thermal sensing. I determined the original case fans' speed and sound by looking up the brand number of the fan listed on Thermaltake's site as being the type of fan used in the Xaser III. As I type this, the processor is running at 54-55 and the case is at 32-34.

To make sure I understand your first suggestion, having more fans intake than exhaust is a good thing to do?

guthmund · 05-28-2005, 10:13 AM

Okay...

So, the side panel fan, which is sucking in air, is right over the processor fan, which is blowing out air? So you've got two fans just blowing at each other?

I can't say I can agree with having more intake than exhaust as it's always worked better the other way round for me, but I would certainly change the direction of the side fan.

There's something going on.. Unless you're sitting in an un-air conditioned room or you've got the system packed in a corner tight, 54-55 & 32-34 seem a bit high especially if you're running 7 case fans.

wombatman · 05-28-2005, 11:23 AM

No, the processor fan blows towards the processor. Also, I am in the center room of my house, which is always hotter than the other rooms, so that could account for some of the higher temperatures.

wombatman · 05-31-2005, 03:18 PM

It occurred to me that I never mentioned that the processer is a 3.2Ghz Prescott, known for running somewhat hotter than most. So the temp of ~55 for that is ok with me. My main trouble at this point is the high case temperature, still sitting around 33-35 degrees C.

guthmund · 05-31-2005, 03:44 PM

Okay, I've been asking around and here's what the collective came up with.

You've got conflicting air flow. The flow from the front to the back is conflicting with the side to top. So, the airflow is probably stalling somewhere in the middle of the case causing the air to just sit there. Does that make sense? I'll admit my brain is a little fried today, so I hope that makes sense.

Oh, and I was wrong about more in than out. It seems you do want more air coming in than going out. And you want air coming in to be at the bottom of the case and the exhaust at the top of the case as it seems hot air rises and despite the relatively small size of most cases, the collective seems to think that it matters. "They" also suggest (especially if the room is air conditioned) setting the case on the floor in a well ventilated area.

wombatman · 05-31-2005, 06:21 PM

Ok, I have it set up now so the Sunon fans are my exhaust--2 in the back, 1 on the top. I have four Thermaltake fans (roughly half the CFM of the Sunon) going--2 in the side blowing on the processor/video card and 2 from the front. The case is about as well-ventilated as it can be given the center-of-the-house heat gathering. Do you think switching the 2 side fans from intake to exhaust would help? That would leave me with 2 intake and 5 exhaust (excluding the power supply fan of course).

Cuatela · 05-31-2005, 07:01 PM

to me it would make sense for the top fan to be intake (since gravity pulls that way anyway) as well as the front, with the side and back doing exhaust.

wombatman · 06-01-2005, 01:02 PM

Top is generally exhaust, from what I've read, because the heat will rise to the top of the case.

Another problem has popped up...my video card is now reading a temperature of 80+ degrees Celsius. I dusted it thoroughly and no change. I think the fan is running, although it is hard to tell with my hand. Any ideas for that (and no suggestions of using one of the Arctic Silencers..I'm trying to save some money this summer)?

And I am now trying using a Sunon on the side as an exhaust of whatever heat it is around the video card, but it is still up around 80 degrees.

MikeSty · 06-01-2005, 01:19 PM

Quote:

Originally Posted by Raptor226

to me it would make sense for the top fan to be intake (since gravity pulls that way anyway) as well as the front, with the side and back doing exhaust.

Ah man, think about what you said!

Cuatela · 06-01-2005, 08:48 PM

Hey, I don't usually do hardware that much...but the heat rising makes sense. I should've known that.

btw, what's the external temperature where your computer is?

wombatman · 06-02-2005, 08:07 AM

External temperature I would estimate at about 75-80 degrees Fahrenheit. I'll find a thermometer and check later. Also, the video card problem has been fixed. Seems there was a lot more dust crammed under the card that was removed when I pulled the card out and really cleaned it well.

kutulu · 06-02-2005, 09:40 AM

Quote:

Originally Posted by guthmund

Oh, and I was wrong about more in than out. It seems you do want more air coming in than going out.

It's not physically possible to have more air coming in than out.

guthmund · 06-02-2005, 01:40 PM

Quote:

Originally Posted by kutulu

It's not physically possible to have more air coming in than out.

Okay, that was worded wrong. Oops.

What I meant was the 'collective' I refer to mentioned that it would be better to have more fans pulling air in rather than blowing air out.

soccerchamp76 · 06-02-2005, 03:17 PM

Whatever way your fans are facing, just make sure you have an air flow pattern established in your case. If your front fans are intake, make sure your rear fans are exhaust to get the cross-ventilation effect going. A exhaust fan on the top of the case would not hurt at all either, although heat at the top of your probably won't affect anything more than your power supply being a bit warmer.

Cuatela · 06-02-2005, 03:33 PM

Quote:

Originally Posted by wombatman

External temperature I would estimate at about 75-80 degrees Fahrenheit. I'll find a thermometer and check later. Also, the video card problem has been fixed. Seems there was a lot more dust crammed under the card that was removed when I pulled the card out and really cleaned it well.

If it's that high, then I would guess the only way to get the temp below 80 is to lower the surrounding temperature. The air can't really cool down before entering the case, and blowing it isn't going to lower the temperature that much.

soccerchamp76 · 06-02-2005, 05:35 PM

80ºF and 80ºC are different.

wombatman · 06-02-2005, 08:03 PM

And, I was able to get the temperature below 65 degrees C on the card after dusting it very thoroughly. So I'm just gonna leave things the way they are for the time being.

05-27-2005, 08:08 PM	#1 (permalink)
wombatman Insane	Air Flow Problem? I've got a Thermaltake Xaser III case. I just replaced some of the fans (the front 2 80mm, the back 2 80mm, and the top 80mm) with Sunon Ultra fans (~50CFM at ~40dBa) to try and lower the case temps and hopefully the processor temp as well (by having more, cooler air moving through). Oddly enough, though, the case temps have actually gone up by about 3 or 4 degrees (under load). The processor temp is about the same. Summary: 7 case fans total, all 80mm, ~21CFM, ~28dBa Replaced the 5 mentioned above with ~50CFM, ~40dBa Sunons Case temp went up What would lead to this?

05-27-2005, 10:39 PM	#3 (permalink)
cyrnel Adequate Location: In my angry-dome.	The fans are pointing the correct direction, no? If you can't remember which pointed where, try both front and lower rear for intake and the rest (plus p/s) for exhaust. More intake (positive case pressure) makes for a cleaner case. I thought that case had a duct for processor air intake? Might have been another version of the side panel. If not, try ducting an intake fan to a processor shroud. Cobble something from cereal box cardboard if you have to just to see if it makes enough difference to get serious. Be careful about cable placement. Get them out of the way, without creating turbulence or interfering with important airstreams. Edit: Another thing - are you sure the new fans are really moving more air? Compare an old and new. Make sure the new intake fans don't have thermal sensors or they'll never come up to speed. __________________ There are a vast number of people who are uninformed and heavily propagandized, but fundamentally decent. The propaganda that inundates them is effective when unchallenged, but much of it goes only skin deep. If they can be brought to raise questions and apply their decent instincts and basic intelligence, many people quickly escape the confines of the doctrinal system and are willing to do something to help others who are really suffering and oppressed." -Manufacturing Consent: Noam Chomsky and the Media, p. 195 Last edited by cyrnel; 05-27-2005 at 11:06 PM..

05-28-2005, 10:13 AM	#5 (permalink)
guthmund big damn hero	Okay... So, the side panel fan, which is sucking in air, is right over the processor fan, which is blowing out air? So you've got two fans just blowing at each other? I can't say I can agree with having more intake than exhaust as it's always worked better the other way round for me, but I would certainly change the direction of the side fan. There's something going on.. Unless you're sitting in an un-air conditioned room or you've got the system packed in a corner tight, 54-55 & 32-34 seem a bit high especially if you're running 7 case fans. __________________ No signature. None. Seriously.

05-31-2005, 03:44 PM	#8 (permalink)
guthmund big damn hero	Okay, I've been asking around and here's what the collective came up with. You've got conflicting air flow. The flow from the front to the back is conflicting with the side to top. So, the airflow is probably stalling somewhere in the middle of the case causing the air to just sit there. Does that make sense? I'll admit my brain is a little fried today, so I hope that makes sense. Oh, and I was wrong about more in than out. It seems you do want more air coming in than going out. And you want air coming in to be at the bottom of the case and the exhaust at the top of the case as it seems hot air rises and despite the relatively small size of most cases, the collective seems to think that it matters. "They" also suggest (especially if the room is air conditioned) setting the case on the floor in a well ventilated area. __________________ No signature. None. Seriously.

05-31-2005, 07:01 PM	#10 (permalink)
Cuatela Insane Location: NC, USA	to me it would make sense for the top fan to be intake (since gravity pulls that way anyway) as well as the front, with the side and back doing exhaust. __________________ Any sarcasm was intentional.

05-27-2005, 09:25 PM	#2 (permalink)
wombatman Insane	Alright, so remembering to plug in the top blowhole helps a lot. Dropped the case temp about 3 degrees. Still seeing higher case temps than before however.

05-28-2005, 09:06 AM	#4 (permalink)
wombatman Insane	The front and side fans are doing intake, the top and back are doing exhaust. I'll see about reversing the lower back fan and seeing what happens. The side panel on this case doesn't have a duct, but it is lined up over the processor, and the 120mm fan I have on the XP-120 heatsink is a Panaflo moving 115CFM, and the temperatures on that are satisfactory (no higher than about 57 degrees C or so). The cable placement is likely a cause of my trouble, as they are all over the place. I'm working currently on improving that. The new fans should be moving more air and are not thermal sensing. I determined the original case fans' speed and sound by looking up the brand number of the fan listed on Thermaltake's site as being the type of fan used in the Xaser III. As I type this, the processor is running at 54-55 and the case is at 32-34. To make sure I understand your first suggestion, having more fans intake than exhaust is a good thing to do?

05-28-2005, 11:23 AM	#6 (permalink)
wombatman Insane	No, the processor fan blows towards the processor. Also, I am in the center room of my house, which is always hotter than the other rooms, so that could account for some of the higher temperatures.

05-31-2005, 03:18 PM	#7 (permalink)
wombatman Insane	It occurred to me that I never mentioned that the processer is a 3.2Ghz Prescott, known for running somewhat hotter than most. So the temp of ~55 for that is ok with me. My main trouble at this point is the high case temperature, still sitting around 33-35 degrees C.

05-31-2005, 06:21 PM	#9 (permalink)
wombatman Insane	Ok, I have it set up now so the Sunon fans are my exhaust--2 in the back, 1 on the top. I have four Thermaltake fans (roughly half the CFM of the Sunon) going--2 in the side blowing on the processor/video card and 2 from the front. The case is about as well-ventilated as it can be given the center-of-the-house heat gathering. Do you think switching the 2 side fans from intake to exhaust would help? That would leave me with 2 intake and 5 exhaust (excluding the power supply fan of course).

06-01-2005, 01:02 PM	#11 (permalink)
wombatman Insane	Top is generally exhaust, from what I've read, because the heat will rise to the top of the case. Another problem has popped up...my video card is now reading a temperature of 80+ degrees Celsius. I dusted it thoroughly and no change. I think the fan is running, although it is hard to tell with my hand. Any ideas for that (and no suggestions of using one of the Arctic Silencers..I'm trying to save some money this summer)? And I am now trying using a Sunon on the side as an exhaust of whatever heat it is around the video card, but it is still up around 80 degrees. Last edited by wombatman; 06-01-2005 at 01:18 PM..

06-01-2005, 08:48 PM	#13 (permalink)
Cuatela Insane Location: NC, USA	Hey, I don't usually do hardware that much...but the heat rising makes sense. I should've known that. btw, what's the external temperature where your computer is? __________________ Any sarcasm was intentional.

06-02-2005, 08:07 AM	#14 (permalink)
wombatman Insane	External temperature I would estimate at about 75-80 degrees Fahrenheit. I'll find a thermometer and check later. Also, the video card problem has been fixed. Seems there was a lot more dust crammed under the card that was removed when I pulled the card out and really cleaned it well.

06-02-2005, 03:17 PM	#17 (permalink)
soccerchamp76 Go Cardinals Location: St. Louis/Cincinnati	Whatever way your fans are facing, just make sure you have an air flow pattern established in your case. If your front fans are intake, make sure your rear fans are exhaust to get the cross-ventilation effect going. A exhaust fan on the top of the case would not hurt at all either, although heat at the top of your probably won't affect anything more than your power supply being a bit warmer. __________________ Brian Griffin: Ah, if my memory serves me, this is the physics department. Chris Griffin: That would explain all the gravity.

06-02-2005, 05:35 PM	#19 (permalink)
soccerchamp76 Go Cardinals Location: St. Louis/Cincinnati	80ºF and 80ºC are different. __________________ Brian Griffin: Ah, if my memory serves me, this is the physics department. Chris Griffin: That would explain all the gravity.

06-02-2005, 08:03 PM	#20 (permalink)
wombatman Insane	And, I was able to get the temperature below 65 degrees C on the card after dusting it very thoroughly. So I'm just gonna leave things the way they are for the time being.