Overheating laptop - any ideas?

[MobileTechie]

I have an HP 520 laptop in running Vista SP2. It runs an Intel Celeron 460 at 1.6ghz

It was reported as slowing up a lot particularly with IE. I've done the usual cleanup job and looked through the logs to see if anything specific was causing the problems. In the course of doing this I noticed the fan comes on hard early after booting up and stays on full thereafter.

Realtemp and Coretemp report the temperature as being 85C on average. It goes up to 89C when you run it 100% for a while and then drops to 83C when idling. These percentages have been checked with Process Explorer in case anything hidden was running.

So I've opened it up and cleaned it out, reseated the heatsink and this has had no effect. Nor has updating the BIOS.

So now I'm stumped. I've had this a week now, asked various people including Scott Moulton, HP and so on and I'm still no further forward. I have to hand it back tomorrow and whilst it's running better than it was, this heat problem is not ideal.

So any help you can offer is very gratefully received.

 

[Hercomputers]

Mobilet,

Is that one of the model laptops that HP had a while back with an overheating issue due to the battery? I remembering either hearing or reading online about HP recalling batteries for this reason. Maybe less than a year ago.

You mentioned you checked with someone from HP? What did he say?

 

[Majestic]

I have an HP 520 laptop in running Vista SP2. It runs an Intel Celeron 460 at 1.6ghz

It was reported as slowing up a lot particularly with IE. I've done the usual cleanup job and looked through the logs to see if anything specific was causing the problems. In the course of doing this I noticed the fan comes on hard early after booting up and stays on full thereafter.

Realtemp and Coretemp report the temperature as being 85C on average. It goes up to 89C when you run it 100% for a while and then drops to 83C when idling. These percentages have been checked with Process Explorer in case anything hidden was running.

So I've opened it up and cleaned it out, reseated the heatsink and this has had no effect. Nor has updating the BIOS.

So now I'm stumped. I've had this a week now, asked various people including Scott Moulton, HP and so on and I'm still no further forward. I have to hand it back tomorrow and whilst it's running better than it was, this heat problem is not ideal.

So any help you can offer is very gratefully received.

You said you reseated the heatsink
But have you removed the old thermal compound and applied new compound to it ?

Majestic

 

[MobileTechie]

Funnily enough the HP guy didn't mention that. However the battery itself is perfectly cool so doesn't appear to be that.

Yes I removed the old thermal compound entirely and used artic silver as a replecement. However my thinking is with you - the only answer that makes any sense is the heatsink not working. That explains the high temps and high fan speed. Maybe something has warped or the screwdown system has failed somehow and the contact pressure just isn't there. I'm going to break it down again and redo it again, partly because I have nowhere else to go with it.

 

[MobileTechie]

I've had the laptop on with the case off and I notice that the last inch of the heatsink, at the fan end, doesn't get very hot. It's as if the heat gets so far long it and then stops? I'm not sure if this is just due to the radiator at the end but I don't think so. Can heatsinks go like this?

 

[RogueTech]

I've had the laptop on with the case off and I notice that the last inch of the heatsink, at the fan end, doesn't get very hot. It's as if the heat gets so far long it and then stops? I'm not sure if this is just due to the radiator at the end but I don't think so. Can heatsinks go like this?

Try a different heatsink, they're relatively cheap and if it doesn't fix the problem just keep it lying around. It sounds to me though like the board might be warped and the heatsink isn't working or seated properly.

Double check to make sure it isn't overclocked as well.

 

[MintyMadness]

I've had the laptop on with the case off and I notice that the last inch of the heatsink, at the fan end, doesn't get very hot. It's as if the heat gets so far long it and then stops? I'm not sure if this is just due to the radiator at the end but I don't think so. Can heatsinks go like this?

If I were in this situation, I would try a very high-grit sand paper on part of the heatsink that makes contact with the processor itself ("Lapping"). While our eyes and fingers may tell us "this is smooth" not every heatsink is made alike, and even the tiniest imperfection in the surface can cause wonky temperatures in processors they are supposed to be keeping cool. You stated you already put a new application of thermal paste "Arctic Silver," which is great! I am going to assume you know the correct amount of thermal paste to use on a laptop processor versus a desktop processor. (too much thermal compound can cause overheating as well, as the paste will essentially "insulate" the processor.)

For my own personal systems, I always lap my processors and HSF's with a 1000 grit paper, buff with a dampened cloth, re-sand with 1200 grit, buff with dampened cloth, then dry, then rub with 99% isopropyl.

If you do end up lapping the heat-sink, make sure you attach the sandpaper to a sanding block or other flat surface. If you don't you will end up exacerbating the problem, rather than correcting it, with an uneven surface.
Last thing, is make sure there are no bits or slivers of the sanded metal left on the heat-sink. These can be conductive, and cause a lot of problems if they get into the wrong place internally.

/$.02

-Jerm

 

[ATTech]

However my thinking is with you - the only answer that makes any sense is the heatsink not working.

It's also possible that a short it causing the processor to heat up and run excessively. This would be typically caused by a defect on the motherboard.

 

[anonymous Mac Tech]

What about drive temps?

 

[MobileTechie]

Drive temps are normal.

I can't explain this heatpipe thing. I understand they are full of a liquid. I wonder if this has leaked and evaporated reducing the ability of it to get heat to the radiator end.

I think I ought to try maybe a copper shim in case it's not contacting. However the only shims I've seen are on ebay and are advertised as being for specific laptops. Anyone got experience of using shims and should I just buy an assortment and see what fits?

I've lapped a heatsink before for overclocking reasons. I don't think it would make this much difference. It's running like 40C over temp.

The heatsink is specific to the laptop so it's not actually that cheap. I'll need to order one.

 

[dannyd]

What temp is the GPU (Graphics) running at?

 

[RedFoxComp]

Is the power jack close to the fan and heatsink? A bad connection to the motherboard can create a lot of heat when it is pushing a lot of power to charge the battery. If the jack is close to the cpu the heatsink will absorb all that heat and you'll get higher temps.

The easiest way to rule that out is to pull the battery and let it run on AC only. If the temps are significantly lower that could be the problem. The other possibility would be a bad battery.

 

[Skyhooker]

Have you checked to make sure the CPU hasn't been overclocked? Not sure if you can overclock a laptop GPU, but if so, check that as well. Other than the things you've already checked, that's the only thing that makes sense to me.

 

[Jeffreynya]

I've had the laptop on with the case off and I notice that the last inch of the heatsink, at the fan end, doesn't get very hot. It's as if the heat gets so far long it and then stops? I'm not sure if this is just due to the radiator at the end but I don't think so. Can heatsinks go like this?

I have seen many heat sinks on HP's go bad, Mostly in the larger developer class machines but also recently in a 8440. I would suggest replacing that.

 

[RedFoxComp]

I have seen many heat sinks on HP's go bad, Mostly in the larger developer class machines but also recently in a 8440. I would suggest replacing that.

How exactly can a block of aluminum 'go bad?'

 

[cdbrehm]

It's very, very rare that a celeron will overheat, especially after you've reseated the heatsink and applied new thermal compound.

But 89C is VERY hot for a celeron. Are you sure the heatsink is making good contact with the CPU?

Either the heatsink is not making good contact with the CPU, in which case you need to introduce a copper shim, or the CPU itself is defective.

 

[cdbrehm]

Funnily enough the HP guy didn't mention that. However the battery itself is perfectly cool so doesn't appear to be that.

Yes I removed the old thermal compound entirely and used artic silver as a replecement. However my thinking is with you - the only answer that makes any sense is the heatsink not working. That explains the high temps and high fan speed. Maybe something has warped or the screwdown system has failed somehow and the contact pressure just isn't there. I'm going to break it down again and redo it again, partly because I have nowhere else to go with it.

High fan speed is an indication that the heatsink and general thermal management is actually working. When the fan on a laptop is very lackluster, that's a good indication that the thermal compound / heat sink / BIOS aren't working.

I'd check first whether the heatsink is actually mating with the chip.

 

[ATTech]

It's very, very rare that a celeron will overheat, especially after you've reseated the heatsink and applied new thermal compound.

But 89C is VERY hot for a celeron. Are you sure the heatsink is making good contact with the CPU?

Either the heatsink is not making good contact with the CPU, in which case you need to introduce a copper shim, or the CPU itself is defective.

Or as I stated, there is a short that is overworking the CPU causing extra heat. I've seen it before; it does happen.

 

[cdbrehm]

Yes, that could be the case. But I'm just saying is check the obvious before you go on an endless hunt for a mysterious short that, statiscally, almost never happens

 

[meanderer]

the fan is spinning, which means the heatsink fan is good. I would check again for the thermal interface between the heatsink and the chips. one thing I usually did was to put a blob of thermal grease on the center top of the chip, mount the heatsink fan, then take it out and observe the grease spread, the farther it spreads the better the mating is. Then I just wipe it up, reapply the thing and remount it. Also if possible, try to touch the heatsink when it runs, that way you can get a feel how the heatsink is holding up. if it is not warm, then you have a bad thermal connection. If it is VERY VERY hot, you may have dissipation problem which depending on the situation may call for replacement because either the fan isn't moving air, or the heatpipe failed.