Best cooling fan location?

[Y2kGoofball]

Hey all

The past few days our PC's been playing up, ie unstable at the best of times.

I thought it may have been a virus or spyware or something, but we seem to be keeping ontop of things

I installed a temp monitor software and the CPU was running at about 50 degrees celcius at the best of times. Ive put it down to these past few days we've been having hotter weather then usual, and this is the first summer since we built the PC

I realise the CPU keeps working at 50 degrees but I also realise it becomes unstable

Now I had a fan at the rear exahusting the air, which we had setup to a manual controller ie so i could turn it up when playing games or similar to exhaust more noise and turn it down when the work loads less to keep it quiet.

Yesterday I vacuumed out the minor dust we had and turned the fan around so it now blows cool air directly into the path the CPU is sucking its air from. I also removed the manual control and replaced it with a heat sensor control, which is designed to sit under the CPU itself, but I just sat it in the heatsink.

Yesterday with the cover on under normal conditions it still ran at 47 degrees, although by then the study was warm (plus my stupid sister always "has to close the door" which with that and the hardware firewall running which is an old slower PC the heat builds up something severe)

This morn I got up and someones been on the PC and it was 42 degrees. I took the cover off for the past 30 mins or so while I looked around at the best location for fans, and I noticed the intake fan slow right down as the temp dropped from 42 to 36!

As I sit here typing its shot up to 38, which has just dropped to 37

Now my predicament ...

I have 2 areas at the rear for fans, as well as at the front

the 1st at the back is directly inline with the CPU ie | {} where the vertical line is the fan and the {} represents the CPU

the 2nd is directly inline with what I think is the onboard graphics chip, its a small heatsink but yesterday was too hot to touch. This is just under the top fan obviouslty!

The front 2 fan spaces are directly inline with the HDD

I dont know how to set it up

Ive read some people say 2 fans sucking in at the front, 1 sucking out the top of the rear and one sucking in at the bottom of the rear

Ive read some say suck air into the path of the CPU (and use the other rear fan to suck onto the graphics heat sink)

ive read only exhaust at the rear and intake at the front, which is why the front slots are low and the rear is high ie heat rises

I just dunno &(

I plan on picking up another one of these heat adjusted sensor fans, probably for the rear, and 2 standard fans for the front

I was thinking of setting it up ... 2 x standard fans at the front to suck air in, across the HDD and into the case

The bottom rear slot use for sucking air in, and putting the sensor in the graphics heat sink so it can auto speed up during gameplay as the graphics heatsink heats up

the top rear slot use for exhausting hot air out from what the CPU has generated, and sticking the sensor into the CPU heatsink so as it heats up the fan blows faster and theoretcially will exhaust most of the heat generated

I'm still not sure whether to have the top fan blowing room temp air into the path of the CPU fan, I suppose its not too good of an idea ie sucking in dust, and if I get air blowing in from the front and from that bottom rear fan it should theoretically cool the air around the CPU air intake, wouldnt it?

Any suggestions welcomed :D

[Y2kGoofball]

hmm well quite strangely I thought I'd manually update my virus defs ... went to right click on the taskbar icon and ... no icon!

Antivirus had been disabled as had updates

I'm a bit sus as to why :confused: Maybe it is a virus thats causing the system to become unstable, although I must admit its been going fine since ive started monitoring the temps and trying to keep them below 40 degrees

Who knows, still any help on the best spot and direction for fans is appreciated :rolleyes:

[chris]

I have the fans in mine set up with two at the front pulling in air, and 1 chassis fan at the back, extracting air, along with a power supply with 2 fans in it pulling air out, and there is another fan right beside the CPU sitting on top of the heat-sink for the dual-power circuitry.

This is close to AMD's recommended configuration. At the moment, the temps in my PC are:

CPU: 44°C
MB: 32°C

That is while I've been using it for work, so it's not too bad.

Yesterday it went up to about 46°C, but it was indeed warmer as you mentioned. It could run cooler if I crank the CPU fan up to 6000rpm, but that is so noisy I can hardly think properly! So the CPU fan remains at 4500rpm, where it still makes quite a noise.

I think most CPU's should be fine to run at 50°C, or at least that's what I was told, but you should keep a close eye on things if it goes more than 55°C, and especially if it hits 60°C, where mine is programmed to shut-down.

[Y2kGoofball]

see currently with the cover off and the rear fan blowing air into the direction of the CPU its sitting at 40, although I am indeed both browsing the internet and doing a virus scan in the background

the software Im using alerts you at 58 degrees (yellow warning) and red at 70 degrees. I remember the Bios is set to cut out, I dunno at what temp coz I cant remember

I was reading they say the AMD will overheat at 80 degrees, although I have witnessed first hand an AMD which had its CPU fan die and the temp recorded in excess of 99 degrees (as its only programmed to go to 99 as most CPUs dont go to beyond 80!). It was that hot it acctually melted the plastic veneer on the office table!

Ok, I might set it up as you said, 2 x front sucking air in, the lower rear one also sucking air in to blow over the overheating graphics heatsink, the top rear blowing out to extract heat :o

[Y2kGoofball]

just reading a how to cool guide

They reccomend for every fan at one end, another fan in the opposite direction at the other

So if you have 2 fans at the front side by side sucking air in, have 2 fans side by side or in my case ontop of another blowing hot air out at the rear to create a wind tunnel effect

So I was thinking more about it, plus I forgot the PSU also acts as an extraction fan.

If I put 2 fans blowing cool air in at the front, I can have the PSU and a fan under that at the rear to blow air out, and the sensor fan in the lower rear chassis fan bay blowing air in, directly onto the graphics heatsink. Theoretically the heatsink isnt hot during normal activity so the fan will be extremely low RPM's and not "upsetting the wind tunnel effect" but when it does heat up ie gaming or movies the fan will auto speed up to keep a constant cool airflow over the heatsink, in this case the hotter the heatsink the faster the air flow in

Problem is this may upset the wind tunnel effect on the CPU, and the CPU would be heating up also during intense gaming?

The other alternative was to try a "ducting mod" theyve got. Its supposed to replace the fan on a heatsink, but my heatsink fan is not 80mm x 80 mm (its 60x60) but I thought my rear fans are 80x80, maybe I should screw the duct to my rear "in" fan to take advantage of its angled design, it should just about be perfectly angled to blow directly onto the graphics heat sink :D ie it wont screw into the heat sink but I'm mainly trying to change the direction of air flow from straight into the centre of the case to directly onto the heatsink of the onboard graphics
http://www.pccasegear.com/prod759.htm

Chris - how do you double up like on your CPU? As ive read series is where one fan is behind another fan, this causes the air going through both fans to flow faster, as the fan behind is being accelerated by the fan in front and vice-versa. They do not move double the air, merely more air through one fan.

Sounds like what i'd like to try on the CPU fan .. seeing as i am going to all this trouble to run cool air past the CPU fan might as well try to make more air flow faster

I just cant seem to understand how the 2 fans are screwed or locked together, because surely the screws arent long enough to pass through 2 fans?

[chris]

I'm not sure how that is done either. You'd probably have to use those little removable plastic clips like what the Lian Li cases have to secure their fans.

Or you could try smaller cable ties.

Another way would be to use some small screws, and an equally small bolt, that might work.

[Vette Boss]

I might be repeating some things that have already been said, but bear with me please.

You want any front fans and/or side panel fans pulling air into the case, and fans at the back pushing hot air out. If your case has a top exhaust fan, that should be mounted to push hot air out too.

Hot air will rise to the top of the case, so it needs to be pushed out by the higher exhaust fans. The coldest air in the room will be right at the floor, so the lowest fans and the side panel fans need pull the cool air in.

Say your case has two exhaust fans in the back, if you set one to push air out and the other to pull air in, the air pulled in will be the air the other fan just pushed out, won't work. Same way if you have two side panel fans. It might seem smart to set the higher side panel fan to push hot air out, but you'll be taking cooler air away from the CPU.

Also, if your wires are pretty messy, get some cable ties and clean them up. Wires are the worst thing in the computer to impede on your cooling setup.

Hope you find my post helpful. Good luck getting your system cool. :)

[chris]

Another thing worth doing is being religious with keeping the room where your computer is clean. That will to a degree take care of some dust and dirt.

[VQ]

I fitted a intake and exaust fan to my case and the box now runs at a constant 25 degree's the CPU as I have said in the past has got up to 60 in 40 degree weather, I plan on buying a Xp2000 CPU as it fits the motherbaord, but i'm running out of time before they stop being sold and then I will purchase Coolermaster Aero 7 fan, or is it jet 7? which ever one is a AMD fan, the case fans I have are Coolermaster daual Ball bearing fans too.

basically, upgrade your cooling fan on your cpu in addition to the rest of the fans because they don't help 100%

[Vette Boss]

VQ: I recommend a Thermalright ALX-800 if you can find one in your area. I forget if it comes with a fan or not. Cooling with those is very good, and the price is reasonable also.

The heatsink is a hybrid with a copper base and aluminium fins. It also uses the regular clips to install, no bolts through the motherboard.

[Y2kGoofball]

theres a few CPU coolers going on ebay, I was thinking of maybe picking up something along those lines

Problem is with the cover off the temperature reduces, today for instance while my sister was doing an assesment in word I had the cover on, where the temp reached 58 degrees before locking up (plus dad had te shites with the noise of the fan in the back)

When I took the cover off it reduced to 45 degrees, with cool air being blown onto it it reduced further to 42 degrees where its been stable ever since

The plan is like Vette Boss said, drag cool air in from the front and blow hot air out from the back, as the internal temperature also affects the CPU temp

Problem is these things all cost money :rolleyes:

But I'm going to tomorrow pick up some fans for the front and rear and see how we go before spending money on a CPU cooler if it does really need it

Problem is with the warmer temps these last few days its been locking up due to overheating,s o if I can get it to run at say 40 - 45 degrees rather then sorta 58 - 60 degrees I'll be happy :D

well see how it all pans out

[VQ]

I recoment also putting the comp in a cooler room, but maybe cutting the front of the case off a bit will help the intake fan? i gotta do soemthing for mine as it isn't as effieceint as it should be.

[Vette Boss]

You might want to cut out the front fan grills. You would need to take everything out of the case to do that.

[Commander]

Hold up. There is a funny thing with fans, be they PC fans, house fans, ceiling fans, radiator fans, rotors on helicopters... whatever. Anyway, you NEVER want a fan to blow air against a suface (like the wall or desk part at the rear of the tower). This just creates a cushion of pressurized air, which basically comes to a head where there is no wind being generated and the fan itself encounters no resistence. This actually allows the fan to gain speed. The increrased fan speed might make you think it is flowing more air, but in reality, the fan is just spinning freely in a low-pressure area.

OK, with this in mind, it can be said that it doesn't matter where the air comes into your PC and where it goes out, so long as the paths of the air flow are unobstructed. If you really hate warm air on your legs, then send the hot air out back somewhere, but construct a simple baffle with cardboard to direct the expelled air away from the discharge fan. In other words, don't allow a fan to blow directly against a flat surface. The same is true for intake air. If a fan is drawing from near a flat surface, the currents will all collide at the intake point, negate one another, and ultimately cause a low pressure, once more resulting in no air flow. Again, baffling will help direct the flow into the case.

For an intersting experiment, try installing some ceiling fans at different distances from the ceiling. You will find that those that are too close to the ceiling will actually spin like mad, but flow absolutely no air. Conversely, fans that are too low encounter too much air resistence, and spin slower, thus delivering less than optimal air flow.

So in a nutshell, when cooling your PC it isn't really so important [i]where[i] the fans are located, so long as the entry and exit paths are unobstructed and are able to flow the amount of air that the fans are able to move.

[VQ]

Yeah, I over sized the orignal holes in them because I couldn't get grills for them so there is very little air loss on that part, but the front of the case gets some air in at, I want to put some cuts in to assist it a bit more.

[Y2kGoofball]

ok guys

Vette, thats still a good idea to cut the grilles out. I never thought of doing that :rolleyes: but it makes sense because theres no reason why ... I mean grilles are only really there to protect loose objects (fingers especially ...) but the front fans are protected by the front cover :D

Commander thanks for the info, it helps explain alot!

Ive been looking for the best way to unobstruct the air flow, and I think ive done it :D

Our tower isnt on the floor, partially because weve just had brand new carpet installed which, with all new carpet, its still got little loose bits everywhere, which we dont want sucked into the case! Also because of convienience and the length of cables and location of other peripherals, ie printer, hardware firewall etc

I recoment also putting the comp in a cooler room Well it is in the study, which is a dedicated computer room so that options out of the question, however that said we are also looking at installing an air conditioner as for some reason out of all the rooms it was the only room to miss out on the ducted air cond (we didnt install it ...) , plus the ducted is too small and stuffed to work efficently in summer, so we can install a small air cond in the study which will blow directly into the front of the house and help the poor ducted in the heat of summer, plus keep the study cooler :D

[Wazza]

Interesting.

Is there a non Asus software, which can tell you what temp your pc is running at? My motherboard is an MSI, and I can see the details in the BIOS, so it looks obvious I can get them on XP, via a proper utility.

My computer has been on for 10min, 6pm at night, room is maybe 17*C.
CPU was on 43 then went to 44, then 45, just in the 1 minute I was looking at it.
System temp is 28*C, and CPU fan speed at 2657rpm. (anyway to make that go faster? have a standard 2.4GhzPIV with fan)

[Y2kGoofball]

I'm using software called "Hardware Sensors Monitor" which strangely enough as the title suggests it gives readouts for any possible sensor on any motherboard because I had problems witht he Asus software

Ok, this morn I spent 4 hours grinding out (yes, I attacked it with a grinder) the rear and front grilles, the rear was just a big rectangle shape anyway (not circular like most commonly used)

I tidied it all up

Went to the PC store, ended up buying my 3 fans (plus my huge sensor fan for the rear) as well as a HDD cooler for $10 and I was talked into a Thermaltake "Silent Boost" for the CPU

Strangely the silent boost is supposed to be for up to AMD 3400+ (weve got 2500+) but since installing it in the last few minutes the temps still risen to 39 degrees and slowly creeping up, without the side cover on, so it'll be interesting to see how well it works

HDD cooler - best 10 bucks I ever spent! my HDD was regestering Temps of 40 degrees to 47 degrees before I left home, I read 50 degrees is a danger temp for mosr HDD's

Simply bolt the HDD cooler to the bottom of the drive, plus it into the power supply (it goes between the power plug and the hard drive). Its reached 29 degrees and seems to be sitting fine, opposed to 40 to 47ish degrees!, although I have deliberately put the HDD in the bay above the front air intakes because the HDD cooler fans can suck the cool air onto the HDD (well you couldnt put it on the bottom bay anyway and in between top and bottom bays obstructs the cool ait flow)

Anyway I wa smainly running the PC to see if I put the CPU cooler on properly, its acctually now cooling down (gone from 38.5 to 38.0 in the last few seconds) so I'll clean up the wiring and see how we go!

[chris]

Interesting.

Is there a non Asus software, which can tell you what temp your pc is running at? My motherboard is an MSI, and I can see the details in the BIOS, so it looks obvious I can get them on XP, via a proper utility.

My computer has been on for 10min, 6pm at night, room is maybe 17*C.
CPU was on 43 then went to 44, then 45, just in the 1 minute I was looking at it.
System temp is 28*C, and CPU fan speed at 2657rpm. (anyway to make that go faster? have a standard 2.4GhzPIV with fan)

Wow.. It runs that cool, with only the standard fan? That's amazing compared to my noisy screamer of a thing which is now sitting at 48°C with the fan CPU running loudly at 4800rpm. It's tiresome.

I'm hesitant to make any major mods to the case however, since it is quite an expensive one.. I'm certain a few extra smaller fans at the back would help greatly, along with removing the dual-power circuit board (the mainboard I have can run with or without it).

The problem with the dual power system is that the little board for it has a fan and heat sink on it, and it radiates heat right beside the CPU! (bad placement of the slot on the mainboard for it).

Y2K: You should have gotten a Thermaltake Volcano 11+ or something like that for cooling the CPU. Those ones work, although they are heavy, and very noisy.

[Y2kGoofball]

I was going too but this one is whisper quiet and seems to be doing the job

The CPU is yet to rise above 43 degrees and, as i said, 2700ish RPM and whisper quiet, and we've been using the system the last hour or so for general internet and that sorta thing

Plus the rooms fairly warm, they reckon it reached 29 degrees here today - 1:00pm 28.9 degrees and I know for a fact their weather sensor is located right on the 2000 Olympic Rowing course, so it also cops the chill factor from the water and has been known to be a few degrees off (but they use it for the news too) and I didnt have the ceiling fan on today so the rooms quite stuffy )=)
Anyway seems to be doing its job :D

[VQ]

did you buy fan covers from the store too y2k? in case someone goes behind the comp and all.

[Wazza]

Just after I posted, I visited the official MSI website, and found the main utility for it. Now it's running minimised, PC been on again for 7min, and current CPU 37*C, and Sys temp, 23*C. My room is probably closer to maybe 13*C now. A bit chilly during winter.

The next thing I will upgrade on my PC, will definately be a new case with larger PSU. Currently only have 350W, and it's not really enough for running floppy, 2 HDDs totalling 200Gb, DVD Rom, and CDRW.. Really need 450+. :)
And with a decent case, it should come with some nice thermaltake fans.

I'll see what my temp is after running computer for a few hours. I know my PC itself acts as a heater for the old room, which was only 2.5x2.5m. A little study. At least I'm in a slightly larger room, approx 3x4m. And have yet to notice the pc warming the room up. =[

[Vette Boss]

Wazza, for the power supply I recommend anything from Enermax. Those are one of the better power supplies you can get, their 431W model should suit you well. I believe that model has fans that run for two minutes after the computer is shut down, helping to get hot air out of the case.

Chris, if you want to you can get a fan adapter for the Spark7 and put a 92mm Panaflo fan on it. That would be much quieter and probably cooler also. :) Panaflo fans are very well known for their cfm/noise ratio.

[chris]

I might just do that, thanks for the suggestion.

At the moment, I tend to use earphones connected to the computer and have music blasting through them - anything so I don't hear that Thermaltake Volcano 7+ scream. (didn't get the 11+ because it wouldn't fit).

I love the Apple Mac computers in comparison because they are nice and quiet, while still having plenty of processing power for the work I do. As much as the PC makers hate to admit it, they have a lot to learn from the Apple computers in many respects.

I think I'm not the only one around here to be converted to the Apple cause, Justin Martin is also a Mac user I think.

I also agree with Enermax power supplies. I've got one of there PSU's in my PC.

[chris]

I just removed the dual-power system board from my GA7-NNXP gigabyte mainboard. (it's an optional part, but came standard on the limited edition version of this board that I have). The CPU temps have gone down slightly.

Now 45°C after a while, and it seems to be staying at that temperature. Although the air-temperature has gone down slightly, but it seems okay.

[VQ]

How come you getting hot days and us Victorians are missng out? weird. Anyway, why do we alwasy need more power for the pcs when the same objects were run years ago on 100w PSU's, I used to run about 4 different scsi hdd's and a cd and floppy on a 100w power supply attached to a 486, what makes the new computers different?

[chris]

More power hungry CPU's and graphics cards are the main culprits.

I must admit, Sydney's warmer weather is nice, as long as it doesn't get too warm.

[Wazza]

Some interesting talk on PSU units-->
http://www.gpforums.co.nz/showthread.php?threadid=216103

Seems some claimed 450-500W power supplies are cheap crap, and a really good 350W one, can do a much better job!
Well I have a really CHEAP 350W.. What's that.. Equivalent of a good 200W? ^_^

[chris]

I've got a really good 350w PSU, payed a packet for it when it was new, but it seems to be alright.

In fact, the Enermax 350w PSU they write about in your link above is the one I have.

[Y2kGoofball]

our PSU is a cheap one that came with the case, 200 W I think. Powers the 1 x hdd, dvd burner, dvd reader, floppy drive and the "case lights" that are on the front (I'll have to post a pic their quite cool!) plus now the 4 fans directly plugged into the PSU

I have to say ours is running quiet - you hear the noise but its not scereaming

After being on for almost 11 hours today the cpu temps sat roughly 44 degrees all day, hdd around 33 - 35 degrees and motherboard 20 - 25 degrees. CPU fan running at 2700 / 2800 RPM (so much for their 2400 advertised speed ^_^ ) and the sensor fan at the rear running at around 2000 odd rpm (it adjusts according to the head in the case where the sensor is)

VQ - I asked but they didnt sell them, but I had 2 spare that I had taken off old power supplies that werent made with the fan in mind ie the PSU casing had a hole for the fan and they had to screw the fan covers on so its all cool literally!

[Wazza]

I wonder how a decent water-cooled system would compare to our fans.

Again, surprisingly, PC has been on for around 5 hours, using photoshop, winamp, uploading digital photos to an online print store, and temp is running a consistent 33*C. Auckland temp tonight is a low of 3*C. Currently probably 10 in my room. CHILLY.

Noisy?
Sometimes my fan starts up, its cranking hard. Sometimes it seems like perhaps the fan is spinning slightly off center or loose, which is giving it a small vibration, which is what the loud fan sounds like. But give the computer i small hit, and it stops. :blush: (Or just wait about 2min)

[chris]

That sounds like a stuffed fan.. Probably it's a sleeve bearing one, and the bearings have gone dry. You could attempt to use some sewing machine oil to fix it, or just do as Y2K did and get another fan like a thermaltake one for instance.

[Wazza]

Yeah, I may leave it for a couple of months, and get a decent case including thermaltake fans, and a decent PSU.

(Start PC up this morning, system temp monitor is in red, 15*C. Must be too cold?) And CPU temp started on 23*C, but quickly made it to mid 30s again