HP Pavilion will not start

[fvdave30]

I am working on a HP Pavilion dv9000 laptop computer. It is the entertainment edition. The laptop starts up and all the indicator lights come on but just as soon as the lights are on and the fan starts it reboots to do this over and over again until it is stopped. I found a youtube video and also documented comments and points to follow that states that this is a video chip issue in which the video chip has become disconnected from the board. I have done the following

• I have removed the battery and tried starting it with the power cord only(no success)
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• I have removed all power and held the power button down for 15 to 20 seconds. (no success)
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• I have checked the ram (no Change)
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• I put in one ram chip at a time in the primary ram slot
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• I put the other ram chip in the primary ram slot
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• I did the same for the secondary ram chip
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• I got a second of the HP logo when in the secondary ram slot but then nothing
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• I tried it on an external monitor with no screen response

My question is "is it really the video chip on the motherboard or is it something else?"
Is there a way to get around this restarting?
Should I follow the instructions to heat the video chip with a heat gun or hair dryer?
Thank you for your help.

[jingda]

At which part does it start to reboot and reboot. The login screen, POST or others?

[fvdave30]

I really do not know as I am unable to see anything on the screen. The screen just stay blank. It is not black as it shows some light emulation on it. I think that goes through the post as for one blimp of a moment once I saw the HP logo. The time frame before rebooting is around 10 seconds.

[eskimo456]

It sounds like it possibly is the video chip.
If you heat the chip with a hair dryer I don't think it would work for very long after. The theory is that you can heat the chip to try to re solder it back to position and get a good connection. I wouldn't recommend this tho.
Check to ensure there are no discs or anything inside any media (I have heard of this forcing reboots).

Failing that Opening the case might be a way to diagnose the problem. If you are unsure or don't feel comfortable then it may be worth taking it to someone.

Usually you can just use a Philips head or torque screwdrivers to remove the bottom of the case, this will then show you some part of the laptop, most probably a fan or 2 and a processor plus some parts of the motherboard. Check for any lose cables and any scorch marks or sign of heat this may help pin point he problem.

Another idea is to remove the hard drive and boot it on a separate computer. The from this find the event logger and see why it has shut down and what messages are displayed. On windows 7 click the start->right click the computer nad opne manage(you will have to be an admin)->Then select event viewer. this will take a little while to show up everything but look for things in the critical section. Possibly put up a log to see if the problem can at least by diagnosed or confirmed it is the GPU.