> I wonder whether it will be possible to suspend the disk and
> pull the fan to make the qube dead silent.

I disconnected the fan on my qube2 some months ago. 
There was heat buildup internally no question about it, way more than I
was comfortable with. Odd/weird things happened subsequently, all of
which I attributed to stuff running hotter than was healthy. On balance,
I decided that the tradeoff wasn't worth it and re-enabled the fan. End
of weird stuff happening, which (I thought) tended to prove my heat
buildup theory. Some folks have gotten away with it, there is some
anecdotal evidence to show it can be done without bad things happening.

Some of the problem had to do with the fact that I had a 7200RPM drive
in there 
which generated way more heat than the original drive.

I don't know if this snippet is worth much to you, "YMMV" as the saying
goes. You may be OK with no fan. It's probably worthwhile to test and
see what happens. 

Regards,
-Colin