Can I just put another fan in the case by mounting to a side panel, and
drilling some holes for ventilation? I can accomplish that, but would
prefer something a little more graceful. Any suggestions?
Thanks for your and others' comments thusfar.
Drilling holes where?
Side panel fans don't do a lot to cool drives, typically they "might" even
decrease flow though the drives, if formerly the air intake was around the
bay but now the suction from the rear fans is no longer drawing in air
there, rather being equalized by that side panel fan. Certainly it can
vary per case though, but generally a side panel fan is not a good
solution for HDD cooling.
Typically to get good HDD cooling you need space between each drive. The
amount of space needed can vary but at least 1 cm is a good idea, more,
even a lot more, is preferable. Then the air intake for the case routes
that air though the drive bay. A common alternate method is an active
intake with a fan, but it is more difficult if the bay isn't deep enough
(designed to hole a fan) or the front bezel isn't deep enough to mount a
fan on the outside wall instead of inside wall of the front.
If you were to use only the upper and lower, not middle drive slot, and
drill many holes in the front wall, in front of the drives, that should
help a lot, but for most airflow though the bay you might need block some
other holes, and therein lies another potential problem, if the bay is
higher up in the case then the lower 1/2 of the case will then have
reduced airflow. For this reason the best drive bay arrangment is as low
as possible, even riveted or bolted to the floor of the case.
Adding a bay would be the best solution. You might find one from an old
case which has a design yielding itself to being mounted, though some OEM
cases don't have suitable bays for doing that, more often plain clone type
cases do. An alternative is to fab your own bay, throw a fan in front if
you like... an example of one I made for an old case:
http://69.36.189.159/usr_1034/gw_case/HDD_bay_fan.jpg
That particular design wouldn't suit your needs since it only holds two
drives, but the same idea, just taking some sheet metal and forcing your
will on it, you can make it as big or little as needed,
http://69.36.189.159/usr_1034/gw_case/prepped for use.jpg
The only caveat with doing something like that is to strip the system down
or be VERY careful to not end up with metal shavings from the hole
drilling/cutting/etc.
Finally, consider that I was only suggesting a potential issue, perhaps
your case cools better than I expect and your drives are already cool
enough. Only you can confirm that and recheck after addition of another
drive.