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CNS
11-03-2011, 04:35 PM
Hello All;

I have read numerous threads about laptops powering off immediately after use, but I'm at a point where I am about to give up on this job. :confused:

It is a HP Pavillion dv5000 with Win Xp Home. Initially, the issue was that laptop was making a humming noise through the audio ports. I took the laptop apart to check for any issues /shorts/grounds but all looked ok.
About 3 months later the same customer came to me and said that now the laptop won't stay on more than 5 minutes, it keeps on powering off. I have booted up in Safe mode and it still powers off so i think its a hardware issue. Also, I did feel that the bottom of the laptop gets hot very quickly, actually within a couple of minutes so I know its overheating somewhere. I take it apart and blow out all the dust bunnies, but still powers off. I added another CPU fan, switched up the RAM, took out the CD/DVD Drive and just booted up with nothing but the HDD and the fan, but still same issue. I am ready to deem this a motherboard issue, however is there anything i have missed? I also did check components and checked the solder to ensure they are all fine..in what I can tell it looks good. PLEASE HELP:eek:

mraikes
11-03-2011, 04:37 PM
Did you replace the thermal compound?

CNS
11-03-2011, 04:43 PM
No, when i put in a new fan I didn't add any thermal compound as I am still troubleshooting this issue. But.... would the thermal compound cause such issues?

mraikes
11-03-2011, 04:46 PM
No, when i put in a new fan I didn't add any thermal compound as I am still troubleshooting this issue. But.... would the thermal compound cause such issues?

Sure, if it was dried out or inadequate the heat won't be drawn off the cpu. That's the very start of the cooling process. So far you've been attacking the end of the cooling process (getting the heat out of the case).

dgast
11-03-2011, 04:48 PM
I quick Google search turns up a forum on HP's support website talking about the overheating issue.
http://h30434.www3.hp.com/t5/Notebook-Hardware/HP-Pavilion-dv5-Overheating-and-restarts/td-p/170844

I had a DV9000 in a couple of weeks ago and found a recall notice on them which involved the NVIDIA gpu overheating, sent the client to the nearest HP dealer to try to get a free replacement based on the recall. Still haven't found out if it happened though, I guess I'll follow up again and let you know.

MobileTechie
11-03-2011, 05:36 PM
To tell if something is an overheat problem: Use CoreTemp or CPU Temp or similar to measure it the temp. If you can't do this then a heat problem almost always takes longer to kick in on a stone cold laptop than on one that has just turn itself off. I.e. cold, it takes 5 mins to turn off but if you then turn it straight back on it turns itself off much quicker. The obvious cause of this effect is the residual heat.

To confirm it's heat problem: gain access to the heatsink, turn the laptop on and give the heatsink little squirts from a can of air-duster held upside down - like this it will dribble liquid gas onto the sink and cool it right down. If it's an overheat problem then the laptop will stay on whilst you cool the chip artificially.

To tell if it's h/w or Windows: user a linux disk rather than safe mode.

Heatpipes stop working sometimes. There is often no external sign they have failed.

To test for a heatpipe problem: gain access to the heatsink and fan and feel the temperature over the chip and then at the other end of the sink, near the radiator. If the radiator end doesn't get much warmth whilst the chip end gets very hot then you know the heatpipe is not functioning. A less accurate test but one that doesn't require dismantling is just to feel the warmth of the air coming out of the laptop (I place my lips near it as they are most sensitive to heat). It should be noticeable warm air. If it's cold air then chances are you have a heatpipe problem or bad thermal interface.

To test for a bad thermal interface (like too much or too little thermal paste: check the temperature of the heatsink vs the motherboard around near the chip. The surrounding mobo will become very warm whilst the HSF stays too cool.

dgast
11-03-2011, 06:08 PM
Maybe an infared thermometer would be a good tool to use. Anybody using anything like this?

http://www.omega.com/ppt/pptsc.asp?ref=OS561&ttID2=g_lossField of View

CNS
11-03-2011, 06:18 PM
no. it would be a good idea but haven't purchase one yet. Does anyone have one or have any opinions on if it is worth purchasing one?

MobileTechie
11-03-2011, 06:53 PM
I have one and it's pretty much a waste of time except for playing with the laser. It's sort of useful for reflow jobs but even then they're just not accurate depending on the surface. I.e. it needs to be matt black for you to get a proper reading.

Your fingers tell you all you need to know.

ray90813
11-03-2011, 08:03 PM
I would start by making sure that thermal compound is on there, and correctly. I had a client with the same problem, she took it to someone before I got my hands on it and they apparently replaced the compound, but there was none upon disassembly. Turns out her initial overheating problem was due to the fact she was using her laptop on the bed. Once I blew out the dusties, replaced thermal compound, and sold her a laptop cooling pad, hasn't had a problem since.

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