View Full Version : heat problem

03-10-2008, 05:30 PM
:DI got a laptop that is freezing,locking up and restarting?
I hear the heat sink start at start up,and thats it. It (the heat sink)shuts of. I'm puzzeld! If the heat sink was brocken, then it wouldn't start at all?

? Mike

03-10-2008, 05:47 PM
Hey Mike,

Do you mean heat sink fan for the cpu in the laptop? If the fan is broken, the laptop will start, but stop after it gets overheated, the heatsink is just heat removal in the form of metal fins on top of the cpu. Normally, there is a fan ovetop the heatsink to help remove heat.

When you say you hear it start and stop are you sure it is not the fan that you're hearing or the hard drive spinning up and then stopping? Did you remove the laptop casing to check where the sound is deriving from for sure?

Finally, does the laptop make it to the windows desktop or stops in the power on startup test (POST)? Sometimes RAM will cause the same type of problems, but there is no sound coming from the RAM. If the RAM is faulty and the laptop does not pass the POST the hard drive will stop and the power will shut off; it's a fail safe protection feature.

Open the laptop, check the fan on the CPU/Heatsink. Should be spining when power is applied. If it's broken, replace fan.

If more then one RAM chip set is oboard; remove all and install one at a time to determine if any is faulty.

Watch the POST for any messages about RAM or Hard Drive.

It's unlikely that the CPU is bad, but dont rule it out...has there been any hard impacts to this laptop. Has it been dropped or handle roughly, and how old is it? Is it still under warranty?


03-10-2008, 09:22 PM
:pGreat stuff J!

When I start the laptop, It makes it to the windows desctop ok. Sometimes it runs for 1 hour some time 2 minutes. It just reboots or freezes. I can feel the heat on top of the laptop. I would think that some fan should start?

The fan on top of the heat sink starts when I turn on the machine but stops and never comes back on?


03-11-2008, 06:42 AM

Okay this sounds like something I read about; if the fan is working and then not, and then it plays sometimes for 1 hour or two minutes...I want to say it has something to do with RAM memeory modules.

Try this first, go to the company that makes your laptop and check for a new BIOS download. You could be having a problem with the BIOS and the Memory Module identification. So, upgrade to the newest BIOS; this should not affect your Windows XP.

Second, after the BIOS upgrade, go into the BIOS and check the power management settings and/or go into windows and check it there. See what the settings are at for battery power. If the laptop is set to shut down after so long to conserve battery, it could be the problem.

In fact, how old is the laptop and battery? Even if it's new you could have a faulty battery. Does the same thing happen when you're plugged into an outlet and when you're not.

Finally, I think it's going to be RAM or Battery now...

Good Luck,


Bob Reed
03-11-2008, 09:50 AM
In most lap tops the fan does not run all the time so you hear it at start up and then it does shut down. This could have something to do with the thermostat in the laptop. Make sure you do not have the vents on the bottom of the laptop covered up. There is a way around this but you will have to open the the laptop. What make and model? You could wire the fan so it runs all the time I have done this for a umber of laptops.

03-11-2008, 12:11 PM
Well.guys.Thanks for all the help.
I took the battery out and guess what started running to fan FAN

So I need another battery?

Thanks for all your help8-)

Trevor Hale
03-11-2008, 12:28 PM
Be careful there radar. In most cases it is cheaper to buy a new laptop then it is to buy a new battery. be sure that is the issue before you proceed to get a new battery.


03-11-2008, 02:44 PM

Normally, a laptop is setup to conserve battery power, so the CPU fan will only come on when the heat exceeds the CPU's operating temperature. Some laptops will run the fan all the time, where others will not.

If you pulled the battery and just used the power supply that fan more then likely is going to run non-stop because you have unlimted power.

The main problem that you discussed is that the laptop is shutting down after so many minutes or hours. Therefore, the problem you're having with this laptop is not totally heat related. You're fan is working as it should; the problem is that the laptop is shutting down unexpectingly.

Like any rechargeable battery, its lifetime is affected in two ways. 1. If you charge the battery and use it, then recharge it when it's low or almost dead. 2. You charge it, use it for a very short period and recharge it, then use it, recharge it again to soon.

The battery gets a charge memory, if is getting recharged before getting too low, it will expect you to do the same again, as number 2 above. So, you will either have to do 2 other things. 1. Replace a battery before its time or 2. invest in a cycler; a cycler will drain a battery all the way down and recharge it fully.

The reason I know this is because when I used to shoot news video for TV stations this would happen to the camera batteries. And, in the RC airplanes that I have it's the same thing. Every now and then I have to cycle the Transmitter and Receiver batteries.

In fact, cell phones do the same thing. If you recharge it before it needs too you will eventually be charging it more then using it...

Since you have not told me how old the laptop and/or the battery is, I cannot say 100% for sure, but based on what you are telling me...I can say you need a new battery. Still, check for the BIOS updates and the power options in the windows/control panel first.

Finally, plug it into the power supply again and then check the power options in windows and look at the power options in the BIOS as well. I have three laptops and one of them needs a new battery now. I just use the power supply because I am not carrying the laptop around; without pluggin it in, the laptop comes on and two minutes it shuts off...same as yours is doing.

One last thing, my wife has a Toshiba and they had problems with overheating. If you change the battery and this continues, you can buy a laptop base cooling fan unit; something like this:



03-11-2008, 10:07 PM
jkcombs,Bob and Trevor Thanks.

I think I will buy a base fan.