My case has 2x 5" bays, both used, and one 3.5" bay, with the HDD in
it. Airflow over the top of the drive is blocked by the DVD drive just
above it, and airflow over the bottom is not much better, although
better than the top. I do have a mounting cage which would allow the
drive to be placed on the floor of the PC, but on its side, and I
don't know how well these drives do on their sides, given what I know
about how they operate (floating heads and so on..) Maybe someone
could fill me in?
We still don't have a good idea of exactly what this case is
like, a verbal description is not as good a a link to a good
picture.
From what you're saying, it sounds as though you have
something similar to an OEM mATX case and have mounted the
hard drive in the external 3.5" floppy drive bay?
The key to having good airflow past the drive in this
position is having the majority of the front case intake
through holes in the front metal wall of the case (behind
the (plastic?) bezel), and most of those holes immediately
in front of the HDD inside the perimeter of that rack, not
outside the rack and lower down on the case wall.
Sometimes it is possible to modify a case to accomplish
this, by drilling many small passive intake holes in front
of that area, or cutting out that area behind the front
bezel, and if necessary putting a solid sheet panel of
plastic, cardboard or metal (well secured), or tape over the
lowest holes to ensure more airflow in past the drive.
Likewise with your description of the case, my description
of doing this must be a bit ambiguous, basically the idea is
airflow follows the route from intake to exhaust and should
be impeded as little as possible, and channeled through the
rack the drive is mounted in. If that rack has a solid
bottom panel that the bottom of the drive practially rests
again, it will not be sufficient for allowing enough airflow
across the bottom of the drive and would take a lot more
work to drill out rivets (if that's how it's attached to the
rest of the case frame) to pull the whole drive rack out
then cut out a lot of the bottom of it. In most cases, this
is more trouble or work than reasonable.
As for the other mounting location further down which places
the drive on it's side, that may be the best option. The
drive head arms and heads float above the platters based
upon the cushion of air created by the minor friction of the
spinning platters, a boundary layer on the platter surface.
Gravity does not have to be oriented perpendicularly for
this to work so the drive does not need to be mounted
horizontally for this reason. Some have speculated that if
the drive is not mounted horizontally, it will create
different areas of wear on the motor bearings and while this
seems true, there is insufficient evidence of whether this
is better or worse for the wear of the bearings over time.
Since many OEMs do mount the drives in a vertical
orientation instead of horizontal, and we have not heard of
excessive failure rates as a result, thus far the evidence
seems to suggest the drive should be fine mounted like that.
However, the same applies as above that in the front metal
wall of the case next to the drive, this is where there
would need be the holes for air intake so that the air flows
over the drive surface cooling it most effectively.
