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~misfit~[_3_] ~misfit~[_3_] is offline
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Default reflowing BGA with a hot air gun?

Once upon a time on usenet Jeff Liebermann wrote:
On Fri, 16 Feb 2018 14:04:33 +1300, "~misfit~"
wrote:

Once upon a time on usenet Jeff Liebermann wrote:
On Thu, 08 Feb 2018 17:37:25 -0800, wrote:

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.

That's a start. However, to reflow the BGA chips on the
motherboard, you'll need to remove the motherboard from the plastic
case. I take photos as dive into the machine. Seems to impress
(or panic) the customer. For example:
http://www.learnbydestroying.com/jeffl/pics/repair/HP%20Envy%20m6%20clogged%20fan/slides/HP%20Envy%20m6%20A10%20CPU.html


Photo of the above heat pipe radiator AFTER I blew compressed air into
the area from the outside. The only way to get the crud out is to
tear it apart.
http://www.learnbydestroying.com/jef...ogged_fan.html


The HP envy that I have likewise must be stripped down to where the top and
bottom shells are apart to clean the fan. This is what the fins looked like
when I finally got the
http://test.internet-webmaster.de/upload/1519009591.jpg
I was fully intending to cut a hole in the bottom case (and make a hinged
door with tape) so I could access the fan / fins for the frequent cleaning
it will require but the fan lifts out *upwards* and is half under the
keyboard.

(In that picture the heatpipe that you can see is the one from the GPU
that's already been past a smaller set of fins [out-of-shot to the right].
Behind that are the two heatpies that come directly from the 3GHz quad core
i7 CPUs heat collector.)

Also, this one way it could be easily cleaned:
http://www.learnbydestroying.com/jeffl/pics/repair/Dell%20Inspiron%201525/index.html
The bottom cover comes off exposing the entire heat pipe assembly,
which is then easily cleaned. Too bad Dell (or Foxcom) designed it
into a crappy machine (Inspiron 1525) with miserable BGA soldering.


I've not seen setups like that on recent machines. IMO manufacturers are
using 'heatsink clog' combined with difficulty of disassembly / reassembly
(with fragile plastic clips and ribbon cables) as a form of built-in
obsolescence. After all CPUs and SSDs aren't becoming obsolete /
underpowered as quickly as they once did...

More later. Gotta run.


Cheers,
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)