A while ago I started this thread about an HP DV9000 laptop that had no
video.
https://tinyurl.com/ndtmko6

The follow up to that story is I sent the board out for repair. Nearly two
months later, I got it back. I reinstalled it and it worked fine....for two
days. Then the video went dark again. I decided the best thing to do was to
order a brand new board and not have to deal with intermittent, old,
connections causing me grief. Now the situation is, as is with many of these
HP boards, how do I keep the processors cool to prevent a reoccurrence of
the problem?

Here are some pictures:
http://webpages.charter.net/mrfixite...orthbridge.jpg

http://webpages.charter.net/mrfixite...0/GPU-shim.jpg

Let's begin with the biggest concern. In the first photo, there is an extra
piece of copper that extends downward toward the motherboard. It's labeled,
"Northbridge 1.5mm gap." That is approximately how much space there is
between the copper and the Northbridge chip when the heat sinks are
installed. On the old motherboard, that gap was filled with a spongy thermal
pad. The consensus is that if there were an uninterrupted piece of copper
between the heat sink and the chip, the cooling would be much more
efficient. By the way, what is that stuff that can be peeled off? Would that
just be regular electrical tape?

Here is a good video showing the orientation of the components.
https://www.youtube.com/watch?v=t9w-khwIj3U
I'm not sure I would stick a penny under the heatsink to fill in the gap but
that's what this particular user did. The other thing I don't understand
from the video is why are shims inserted under the CPU and GPU if they
already come in contact with the heat sink?

In the second photo I linked, you can see the heat sink for the GPU. There
is black tape attached to the heat sink. Does that help dissipate the heat?
Is that there for electrical insulation? Finally, the motherboard came
shipped with a "bonus" copper shim. It's too thin to help with the gap in
the Northbridge chip. Referring back to the video, the user put one shim
under the CPU, and another one under the GPU. I decided to put the one shim
I received under the GPU since that seemed to be the cause of the failure.
What makes more sense to me is to fill in the Northbridge gap with copper
shims (is it ok to stack them if I can't measure the exact thickness before
I buy them?) and leave the CPU and GPU as is. What do you think about this?

Thanks for your replies.
--
David Farber
Los Osos, CA