Hello
fat & others:
I can't cite anything specific. I am, however, of the same opinion and at the same level of info as
fat. I agree in particular with "
cooler is better" and the paragraph that starts "As a reference on a cold day ...". My HDD temperatures run at right around those levels. When they go above 40C I add some additional cooling.
Here's my setup: 3x 3.5" HDDs in a Thermaltake cage with a 120mm fan at the front. I used to have my NL server in a mid-tower case, but about 6 months ago completely changed over to a different philosophy (SuperMicro rackmount). While the 3xDrive cage was in the mid-tower case, HDD temps were never below 38, even on a cool day. So what I do now is to leave that cage EXTERNAL to the rackmount case (with regular IDE and SATA cables routed through the open PCI slot). Allows for much better airflow to the drives. The whole setup (together with two other servers and a large capacity UPS) is in a double-sliding-door-closet downstairs in the utility room (washer/dryer). What I mean by "add some additional cooling" when things get warmer ... I crack-open the sliding doors on each side and a desk-top personal fan adds circulation by blowing air out on one side.
Current temps/setup: sliding doors are cracked open, desk fan is OFF, two servers (out of three) are running, ambient (outside of the closet) is about 72F. The three NL HDDs are running at 34/34/35 respectively. By early evening (today's outside temps will run around 90F+ and I avoid turning on A/C in the house) I will be turning on the desk fan and HDD temps will rise to around 39/40 with ambient (outside of the closet) around 82F.
Conclusion: Although the "5C lower adds 50% lifetime" seems a little high, I believe the general trend, and -- knowing what I know about and long years of experience with electronics -- I am in agreement with "cooler is longer life" and I strongly recommend a cage with fan or individual HDD coolers ($8-$12) for
EACH HDD you have that has important data on it.
Georg