S
Sham B
Is this a manufacturer dependent issue, or are they all subject to
poor assembly ?
No its a design thing, dependant on what the manufacturor puts between the GPU and original sink.
some cards use one of those awful pads between the GPU and sink. these are petrochemical based, and
work by melting when there is heat (they are solid when cold) and work best with a slight gap to
live in (if there is no gap, the pad gets squeezed out over - albeit long - time).
Other cards use a paste, which needs a much smaller clearance, or none at all. Paste is designed to
harden over time and doesnt get squeezed out, so no gap is required. In these cases, the shim is
almost level with the GPU.
My Connect 9500 pro had a pad, and the shim had a slight clearance. My Sapphirre 9800 pro had
thermal paste, and no clearance at all.
Given that most users will add paste when they put on a new cooler, the low clearance shims are
desirable. If you have a high clearance 'designed for a pad' shim, you have a problem, because the
shim was not designed for paste, and the clearance is too big for best conductivity.
You have two choices;
1. remove the shim. this defeats the original point of the shim, which is to prevent the sink
crushing/cracking the GPU chip due to uneven pressure (they are on pretty tight in many cases), or
2. accept the slight clearance and fill it with paste.
the trouble is, of course,that most people want to replace the stock setup with an arctic cooler,
and the arctic cooler is larger than the normal heatsink, and somewhat heavier. You *really need*
the shim in this case, because the pressure needed to keep the arctic attached to the card is more
than the stock cooler (which typically weigh less than a quarter of the arctic.
Although some people remove the shim when adding an arctic, the consensus seems to be that it is a
little dangerous to do this, and it is safer to leave the shim on whatever the clearance. some
people also decide to take the shim off and sand it down a little (you only have to sand it down a
little to solve the problem).
IMO, the issue is much ado about nothing. On the 9500Pro, I simply filled the gap with paste, and
got a measurable increase in max OC, which was around the same as everyone was getting. You prolly
lose a degree or two through the gap if you are using something like arctic silver, but that still
gives you far better cooling thatn the stock cooler, so its not a big worry and the change of cooler
is still worth the effort
HTH
S