Re: Computer turns on and then just dies

s|b <[email protected]> wrote:

> On Thu, 21 Nov 2024 15:58:30 -0500, Paul wrote:
> 
>> "flip the switch... standby power led on ASUS F1A75... stays on for a bit and then dies"
>> 
>> The power supply consists of two halves.
> 
> It's a bit too technical for me, but I appreciate the response. I'd
> expect the PSU to either work or not. Is the behaviour that I'm
> experiencing possible with a broken PSU?
> 
> I'm going to replace the thermal paste of the CPU first and see what
> happens.

Make sure to use non-metallic paste.  Use ceramic.  Since you're not
overclocking, you won't achieve a one to three degree decrease in
temperature, anyway.  Not overclocking already reduced heat generation.
Also, make sure it is thermal PASTE, not thermal adhesive which is an
epoxy.  You might even go with a thermal strip aka thermal pad for less
mess.  Although not as efficient as paste, strips will work well enough,
especially in non-overclocking scenarios.  Way too many users gob on too
much paste resulting is less than an ideal mating between CPU plate and
heatsink. More is NOT better.

You'll need a piece of mylar or other thin plastic to apply the paste.
A credit card is too rough on its edges.  You want a shear coat, not an
opaque coat.  After pressing the heatsink to the CPU plate, and before
clamping down the heatsink, rotate the heatsink to ensure the paste gets
distributed across the CPU plate.  You can watch Youtube videos to get
techniques and suggestions.  However, even this guy put on way too much:
https://www.youtube.com/watch?v=m7x2sUt0mqo.  Yet his moniker claims he
is from Arctic which is the pervasive leader in after-market pastes.
About a quarter of what he applied is needed.  Of course, when using the
plastic plate to watch the spread, probably about half of the paste
ended up on the plastic plate after removal.  Here's another guy gobbing
on way too much thermal paste: https://youtu.be/a0LlMDk_ljQ?t=12.

I've seen many techniques suggested for applying the correct amount of
thermal paste.  One is to use a piece of thin mylar to spread around the
paste to coat a thin layer you can see through.  Another is to put one
drop in the middle of the CPU plate, or 5 tiny drops in the center and
at midway to the corners, to push down the heatsink to rotate and spread
the paste.  If any oozes out paste the CPU plate, you put on too much
which also means there is likely too much between CPU and heatsink.

You'll need isopropyl alcohol and a plastic scraper to remove the old
paste.  Make sure the CPU plate and heatsink are devoid of any old paste
or thermal pad, and are clean.  After cleaning, keep your fingers off.

Considering your lack of electronic test equipment, I suspect paste
might not be the way for you to go.  A thermal pad gets squeezed between
CPU plate and heatsink, won't ooze out, and liquifies (melts) under
pressure and heat.  Considering how many users apply way too much paste,
and if not overclocking, a pad is just as good.  I've never gotten into
pads, but https://www.youtube.com/watch?v=2BhKx0iQ4K8 and
https://www.youtube.com/watch?v=niAQs8dZohE look interesting.  Despite
the claim reusability of the graphic pad, I'd never reuse one.  I'd
replace it just I would replace paste.  I'm not building and rebuilding
hundreds of boxes.

Personally I'd go with the PSU substitution suggestion first.  The load
a PSU can handle with proper regulation varies with age, and crappy PSUs
age faster.  Replacing thermal paste isn't a job for a newbie.  I always
lap the CPU plate and heatsink to get them as flat as possible for best
mating since metal-to-metal contact is by far the best method for
thermal transfer.  However, rare few users lap their CPU and heatsink.
I don't overclock, but do want thermal transfer to work best, and want
the least amount of paste since it also ages.  

Although the focus has been on the paste, another facet of concern is if
the clamping of the heatsink is even.  You don't want to cinch down one
side more than the other.  That will squeeze out more paste on one side,
but leave too much on the side with less pressure.  You want paste to
substitute for air, not thermal paste to be the primary transfer media.