# (Resolved) dell laptop fan problems



## fallen00sniper (Jul 17, 2007)

i am also having a fan issue and nothing in bios for temps or fan speed, i have a dell latitude c840, a13 bios latest dell shows, hope this topic isn't dead, just this week i bought a replacement mainboard (used with guarentee it is 100% good) as the original had bad hdd controllers, and both fans do work, they come on a few times then stop coming on again ever i have reached 81c (speedfan), the odd thing is the fans are reported to be running (3 fans, but only are 2) with windows xp pro sp2 what appears to be a intake fan runs, ubuntu linux ultimate gamers edition the fan that appears to be exhaust runs, oddly enough ubuntu seems to run the fan whenever the cpu / acpi reaches 55c - 65c, i am confused by this and cannot figure out why only one fan will run in either OS, and why xp fails to run the fans, and i can't find this intel speedstep, did find the fix however, but have not tried flashing the bios.

please help i have spent a lot of money refurbishing this laptop for my little brother.


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

correction, both fans seem to not work at all anymore, thanks to the a/c and a cold basement it is idle at 61c and i could not find the edit post button lol


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## TheMatt (May 9, 2006)

*Re: dell laptop fan problems*

Try another monitoring utility. Download MobileMeter and see what that says.

To enable Intel SpeedStep, set the power scheme in Windows XP to Portable/Laptop. I am not too familiar with GNOME, so you will have to look around in the settings in Ubuntu. Make sure ACPI thermal management or processor throttling is enabled.


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

i don't know much about linux so, i think i am going to have windows on this laptop the whole time, the power scheme is set for when its on ac never off, but dc 5 minutes off, and now they stopped coming on at all, should i flash the bios or is the board gone south the first week i got it?


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## TheMatt (May 9, 2006)

*Re: dell laptop fan problems*

Let it sit for awhile and then turn it on again. See what happens. I would take it to a shop next time or buy from a reputable manufacturer so you you are guaranteed it will work or you will at least have a good part.


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

well in the mean time what can i do to cool it? i'm going to try to use ubuntu and see if the fan turns on with my live disc, but if you know any terminal for the fan settings please let me know. and thanks for helping out.


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## TheMatt (May 9, 2006)

*Re: dell laptop fan problems*

Your best bet is to get a cooling pad. You can usually pick up a good one for around $20. These are my favorite ones:

http://www.newegg.com/Product/Product.aspx?Item=N82E16834999336
http://www.newegg.com/Product/Product.aspx?Item=N82E16835192013


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

i will look into buying one sometime if it comes down to that, i tried running my live disc again and the fan(s) did not come on, so i got a bad board i suppose, unless it is something as simple as bios problem, talking to the guy i bought it from maybe he can help out a little on it.


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## TheMatt (May 9, 2006)

*Re: dell laptop fan problems*

Sorry for the bad news, but I think you are better off getting a new laptop. It will probably be cheaper. The board may have been damaged during transit.


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

i was in my bios today and one or both fans turned on, suspected problem xp...maybe vista would run the board better or worse, not sure what to do. not giving up either.


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## TheMatt (May 9, 2006)

*Re: dell laptop fan problems*

XP would be a better choice, especially on an older laptop like that. Can you boot into Windows?


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## kodi (Jun 30, 2004)

*Re: dell laptop fan problems*

When your temps reach 81c does the computer shut down (it should ) if not I suspect a common fault with Speedfan that it allocates the wrong sensor temp to the hardware.
Post a screen shot of your speedfan readings.
I don't think your fans should be running all the time, only when needed.


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

i can get into windows, and in the bios i disabled the power settings for ac, but i restored them and now the same fan is running and am using a program to control the fan speed manually, but the exhaust fan isn't running still, i am holding around 40c now i got the proggy off diefer.de it seems to be working good, but one fan short of full cooling level, i also cleaned and put a little paste on the cpu that seems to helped a lot about 20c a lot lol, any ideas on the reason one fan will not turn on?


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

kodi it turns off around 80-90c somewhere in between, but speedfan has a check box for dell notebooks, and it saw my acpi and cpu seperate, but they were both very hot.


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## TheMatt (May 9, 2006)

*Re: dell laptop fan problems*

Maybe this can help.
http://www.diefer.de/i8kfan/index.html


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

thats the program i am using now, but only one fan runs even when set to turn on with that program, like i said before with ubuntu the other fan works and not the one that runs with xp, its a little crazy.


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## TheMatt (May 9, 2006)

*Re: dell laptop fan problems*

With the cooling pad, it should be fine. Keep the temps below 70 degrees under full load and you will be all set.


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

well thats the odd thing, the fan stopped running it got to 60 came on the 70+ and it didn't come back on...something isn't right between the xp speedstep and the fan controllers or something, i am also stuck at 1.2ghz and 122mhz fsb when i should be getting 2.0ghz and 400mhz fsb...the laptop is designed for xp, but the stuff just isn't working right.


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## kodi (Jun 30, 2004)

*Re: dell laptop fan problems*

Check the fan for loose wiring/connection on fan and motherboard end also see if it actually works or has died


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

thats the thing i plugged them in and ran a linux live disc, the exhaust runs with linux and intake with xp, so i know they both work.


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## TheMatt (May 9, 2006)

*Re: dell laptop fan problems*

What temperature monitoring software are you using? It is probably incorrect.

The reason it is running at a reduced speed is because SpeedStep is slowing down the processor when it is not under load. As long as it is at the reduced speed, the processor is not under load and is likely cool.


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

i am pretty certain i now have the problem resolved as far as one fan running, intel cpu id shows 400mhz 2.0ghz and i am staying at a cool 40c in a cool basement, i would say its about 65-70f down here, but all i had to do was get my power setting for when things turn off set right and now everything seems to work fine, pcpitstop.com gave me a good score and passing flag on my cpu and ram this time around, so basically bios and windows power settings were the problem, but the issue with the exhaust fan not running is still a mystery. maybe someone will happen a long with a theory on it since in linux i get a opposite effect the fan that does not run in windows runs in linux, but the fan that does run in windows does not in linux, so close to solving it :laugh:


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

oh and that utility shows my cpu running at 1198mhz with little or no load, so maybe it is from the adaptive power setting i have it set to, wish i bookmarked the page that helped explain speedstep.


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## fallen00sniper (Jul 17, 2007)

*Re: dell laptop fan problems*

well the other fan has been running all along lol, just never noticed, but it working and thanks guy for helping me to find the solutions.


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## TheMatt (May 9, 2006)

You're welcome. That must have been a quiet fan if you didn't notice it. :laugh:


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## fallen00sniper (Jul 17, 2007)

actually it runs a little louder but every time i looked when i thought the fan got faster, the other must have stopped, but the odd thing is i stressed the system with americas army and a punkbuster update and the fans went off and didn't come back on at all hit 82c before i got it shut down, so i know it has a limit to how far it can go.


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