personally, i have never seen a heatsink going bad.
but you may want to replace the heatpaste - and make sure the heatsink is mounted flat on the cpu !
you can monitor fan speed with http://www.almico.com/spee
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Browse All TopicsI am experiencing a problem with the dell 8400 where the fan speed is way above normal. I replaced the heatsink based on many postings on the internet that say this model has a problem with the heatsink going bad. There has been no improvement. When the computer starts up the fan speeds up, the air is cold, there are no lights lit on the back of the computer and their is no signal seen on the monitor. I am looking to change the fan or the motherboard next, but am unsure if this will help.
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personally, i have never seen a heatsink going bad.
but you may want to replace the heatpaste - and make sure the heatsink is mounted flat on the cpu !
you can monitor fan speed with http://www.almico.com/spee
The heatsink problem is all over posts on the internet, for the particular Dell model 8400, using a chipset that was only used for a short time because it ran so hot. I should have put a program that monitors the temperature as well as something for the fan, what you describe above when the computer worked intermittently. It was working when I gave it back to my friend, but then it died completely. I have 5 Dells at home, 3 used, never ran into this problem. It turned me away from Dells. I think the first poster could be correct in that when I gave it back to my friend, in ran hot and damaged the cpu. None of the parts from this Dell match my other Dells.
FYI
Check out these posts
http://www.howtofixcompute
http://www.techsupportforu
" own a Dell Dimension 8400 with a Pentium 4 3.0ghz processor. 775 socket i think it is. my problem is anytime i use a program my cpu's fan blows hard...very hard. It almost sounds like a jet. from what ive found out on the dell forums is that the heatsink dell first used was defective"
There was no problem with the chipset on that board getting too hot. - Wives tale.
Same chipset used on many boards with no problem.
If it gets hot on that board then it's a board design problem.
Yes, the heatsinks go bad.
It's a heat-pipe heat-sink and the pipes leak reducing the heat transfer to the fins.
The 8400's also sometimes have an issue with the 4-pin "P4" connector contacts burning.
If they are charred then your CPU isn't getting power.
.
I know exactly what I'm talking about and the people that wrote those 'articles' are idiots.
If you are going to take advice from places like in your example links you might as well get advice from "Geek Squad".
They are at the same level.
.
As to the chipset on that board the TDP is only 13.5 watts.
http://www.intel.com/Asset
A fan isn't even needed.
Like I said it's a defective heat-sink design. [Or QC.]
The gas leaks out of the heat pipes.
The gas is the 'coolant' just like the water in a car radiator.
What happens to a car's engine when you drain all the water out and drive it?
Same-Same with the gas leaking out of the heat pipe.
.
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by: RartemassPosted on 2009-11-01 at 14:42:26ID: 25715964
I'm assuming that sicne you've replaced the heat sink it isn't under warranty anymore.
The fan shouldn't be the culprit and you would most likely be wasting your time replacing it.
Assuming the heat sink has gone bad it may have heated your CPU too much and damaged it. Checking the CPU would be a good place to start. Do you have another CPU that you can put in to test?
This could also be a video card, RAM, or motherboard issue. May even be the power supply not delivering enough power. From your question I think these are a long shot and the CPU is the cause.
If you can't test the CPU, I would try the following just in case:
-Try another power supply that you know is working.
-Try another video card from another PC, or try the video card in another PC. If same thing happens with other video card then that isn't the issue. If the card does the same thing in the other system then you know it is bad.
-Take the RAM out one stick at a time. Make sure that each RAM stick is tested. Make sure you reseat them correctly after the tests.
Replacing the motherboard