"jamie anderson" said:
Hi people,
I've just changed heatsinks on my XP2500+@3200+ & MBM5 is giving me unusual
temps. The CPU Socket temp is about the same (which is a little
disappointing in itself) but the CPU Diode sensor is reporting temps about
10deg C higher than it did previously. It used to report a bit below the
Socket censor, now it's 7-ish degrees above. Everything seems stable
still...
Is it something i need to worry about?
Mobo is an Asus A7N8X-Del 2.0
Thanks for any advice you can give me.
On some heatsinks, the "contact patch" only lines up with the CPU
die one way. If the heatsink is rotated 180 degrees, it only
touches part of the die.
So, remove the heatsink and make sure the contact patch is centered
on the die. Also, when using paste, you want a thin coating, just
enough to fill voids (air gaps). One technique to test, is to put
a dot of paste the size of the head of a pin, lower the heatsink
into it, and see how much it spreads. You can use that to gauge
how big a dot of paste is needed. Too much paste would tend to
insulate a bit.
The heatsink should have been primed with paste before installing
it. Applying paste to the heatsink, fills the voids with
compound. The paste should be rubbed in with a sheet of plastic,
as you don't want your finger prints and oils to fill the
gaps in the sink. If you don't prime the heatsink, the air gaps
in the heatsink might not get completely filled. Once the
heatsink is primed, you wipe off the paste, as you only want
the actual paste application on the die. You don't use solvent
while wiping the heatsink - you are removing all the paste on
the surface, but leaving just the residue filling any
imperfections in the surface of the heatsink. (There are some
heatsinks, like swiftnet.com heatsinks, that have a mirror
finish. Don't expect much paste to adhere to one of those.
The heatsinks that would benefit most, would be crudely finished.)
Pastes with particulate in them (AS3,AS5,Ceramique) have
"settling times". The final temp isn't reached for a couple
of days after application.
My suspicion is your processor is not fully seated in the socket.
I remember my first modded board, the processor socket had a
metal arm on it, and the arm actually made contact with the
heatsink I was using. It took 30 minutes of work with a
metal file, to make enough clearance for it to fit. Ever
since then, I've installed heatsinks outside the case, so
I can visually inspect the fit of the heatsink. I can look on
all sides of the processor, and verify there is the same
clearance between sink and motherboard, on all sides. This
technique (installation outside) only works if your computer
case has clearance to fit the whole assembly into place.
Some computer cases have a brace in the center of the opening,
that only allows the heatsink to be installed after the
motherboard is in place. A screw mounted heatsink is good
for those, as they are easier to install than one with clips.
But you really cannot tell whether they are seated properly
or not, until you turn them on.
HTH,
Paul
)