"Ablang" said in news:
[email protected]:
I just inherited a K6-2 300 Mhz computer, but the CPU fan & heatsink
keeps falling down off the CPU, which means that the thermal paste is
no longer sticking.
Does anyone know a good place online where I can buy this cheap, or
perhaps someone has ideas for other ways of keeping the fan &
heatsink in place (vertically)?
Thermal paste does NOT stick anything together! It is used to fill in
the microscopic gaps in the microscopic irregular surface to provide
maximum thermal transfer between two mating surfaces.
Thermal *adhesive* is used to permanently bond a heatsink to a chip's
heat plate. Thermal adhesive does not have a high a thermal transfer
rate as thermal paste (unless you get really poor grade paste). If the
thermal paste has degenerated (which means it wasn't mixed in proper
proportion or some chemical destroyed it), you'll have to clean both
surfaces and use new thermal adhesive.
Thermal paste is best for thermal transfer. If there is a means of
mechanically affixing the heatsink through the use of clips or pins then
use them and thermal paste. If there is no means to affix the heatsink
other than to glue it, get some thermal adhesive (and, obviously, clean
the surfaces before attempting to re-glue the parts - and follow the
instructions!).
Thermal paste comes in various qualities depending on how much you want
to spend for what rate of thermal transfer. Artic Silver 5 is probably
the best although Artic Silver 3 is near as good. If you're thinking of
overclocking then use those. Otherwise, Artic Ceramic, Artic Alumina,
and many of the branded compounds are okay for normal use.
http://snipurl.com/5z6r has some paste and adhesive products, but you
can find it all over at lots of online vendors and in stores.
Make sure you clean off the old paste thoroughly. Use isopropyl alcohol
and Q-tips to scrub the surface and clean it completely. Don't leave
behind any threads from the Q-tips. Don't touch the cleaned heatsink
and CPU surfaces due to the oil on your fingers; if you touch them,
clean again with isopropyl. Just don't goop the thermal paste/adhesive
on so it is a thick layer. Neither conduct heat as well as metal. You
want as much metal-to-metal contact as possible with the paste/adhesive
filling in the microscopic gaps or due to a mismatch in concavity in the
surfaces. Put a dot in the middle and spread out with a thin and flat
piece of plastic or stiff thick paper stock. It should look transparent
when applied thinly, leaving only about a 1/32-inch uniform layer.
Press and moosh the heatsink around in circles to squeeze out as much
extra paste as possible and to remove air bubbles.
http://www.pcstats.com/articleview.cfm?articleID=378
http://www.articsilver.com/instructions.htm