Should I worry about WD REDs running 40C on a mostly idle machine?

[rogerh]

Interesting. I just toured a fresh air modular datacenter. They raise temps to remove humidity. I suppose that's different than condensation, as yes, iced drinks form condensation quick in warmer air in my experience.

If air has a very high *relative* humidity then raising its temperature makes it less likely to condense on things, but only as long as the things are warmed up too. There is only scope for that if the original air temperature is not too high. Otherwise, the warm air has to be run through an air conditioner to dehumidify it by actually removing water, and you have to keep the fresh air out of the building.

Edit: then it is fairly obvious that the cold air straight out of the air conditioner is saturated (high relative humidity) and it has to be allowed to warm a little before being allowed into electrical equipment. So you would see condensation if you ducted air conditioner output straight into a server.

 

[mjws00]

The quick and dirty way to add that ac might be a simple cardboard box or wooden if you are so inclined as an external enclosure. All components see the same ambient air temp... no moisture issues. You let the case do its regular cooling moving air as usual. Just consider it your own personal datacenter.

Don't have that case but if there is any venting not cooling drives you might be able to block/seal and get flow where you want it.

 

[pjc]

Back to the original question: 40 seems high for idle on a low-RPM drive. I have 7200 RPM drives that idle at 33 and camp out at 35 when reading without seeking. And as others have pointed out 40 degrees dramatically increases the likelihood of drive failure.

You don't have a lot of leeway, though, if your ambient air temperature is 30-35C (86-95F!). We're normally around 24C (75F).

It seems like you either need substantially increased airflow (louder fans), or you need to plan for high drive failure rates (RAIDZ2, etc.).