On Thu, 08 Feb 2018 09:17:52 -0800, Jeff Liebermann
wrote:

On Thu, 08 Feb 2018 08:09:32 -0800, wrote:

I have a laptop that is acting really weird. It's an older ASUS,
probably ten or twelve years old. It was plugged in, closed, sitting
on a table. It worked fine a few days before the problems started. The
display keeps shaking. The machine takes forever to boot up. And then
acts weird. But if I push down hard on the lower left side of the
machine it works fine. As long as the pressure is kept up and in just
the right area.
I spoke to my son about this problem because he knows more about
this kind of thing than I do. He said it sounded like a video card
problem that he and some of his computer whiz friends have run into.
Apparently the video processor can get too hot and the BGA under it
can start to debond.
He has a hot air rework tool and he said I might be able to reflow
the chip. Is this something that a rank amateur can likely do?
Eric

We all have to start learning somewhere. My domain is
LearnByDestroying.com which should offer a clue as to how I start
learning. If you've never worked on a laptop before, your problem
will not be the hot air reflow, but rather the disassembly and
reassembly. Spare screws, mangled flat ribbon connectors, and broken
plastic are common. I suggest you use a digital camera to record the
disassembly to help with the reassembly. You might be lucky and NOT
need to remove the motherboard from the case, but that's not typical.
Before you blow dry your machine, you might look inside, around the
lower left corner, and see if any connectors have come loose. Also,
find an air compressor and blow out the dust, especially around the
fan.

There are YouTube videos showing how to use a hot air gun to reflow a
BGA.
https://www.youtube.com/results?search_query=hot+air+bga+reflow
Make sure you build a heat shield out of aluminum foil to prevent
melting nearby plastic parts. Practice on scrap PCB's before
attempting to fix the unspecified model Asus laptop. It's quite
difficult to tell if the low temperature solder balls have reflowed.
I'm undecided if liquid flux does anything useful.

Good luck.
Thanks for the advice Jeff. And the link. I did take this machine
apart once about 5 years ago to replace the hard drive. That all went
fine. Your "unspecified model ASUS" remark made me laugh because
when I was typing out the original message I realized I didn't have
the model number on hand and knew at the time that I really should
have included it with my post. I always seem to get caught.
Thanks Again,
Eric