Hopefully I'm just being paranoid, but better safe then sorry, yeah?

 

What are acceptable heat ranges (especially the upper limit) for drives in an unRAID box (or any computer for that matter)? 

 

I know there is probably no simple answer, since manufacturers claim different acceptable drive temperature ranges for different drives.  So is the safest bet to look at the manufacturer's recommendation for each drive, then take the lowest of the upper limits to be my working limit?  I'm hoping to draw from many of you hero members' collective experience as to generally safe temperature thresholds that will apply to most drives.

 

I haven't had any problems yet (that I know of), but since summer is picking up with gusto, I want to be sure my unRAID box will be OK.  During normal operation and parity checks (which generally take place in the evening or nighttime), I see drive temperatures in the range of 30 - 40 degrees C.  However, on a few occasions I have seen temperatures above 40 degrees, and I believe the highest I've ever seen was 48 degrees C.  I am using a case designed for good airflow (Antec P180), however I have all 3 fans set to low speed, for near-silent operation.  One fan is dedicated to the 4 drives in the lower bay as well as the PSU, so I figure those drives are probably my coolest ones.  Its the 4 drives in the upper compartments (2 in HDD bay, 2 in the 5.25" bay via 5.25" to 3.5" brackets) that I'm more worried about, since they don't have any dedicated fans.  The two other fans in the case both cool the CPU, one venting through the rear and one through the top.  Should I crank 'em all up to medium fan speed?  I will notice the noise at that speed, but obviously its worth it to protect my data and prolong the life of my drives.

 

In a somewhat related query, I have reasoned that 'green' drives (like my two WD 1 TB green) produce less heat since they spin a bit slower.  Therefore it is OK to put them in the less cool area of my case, whereas I should put all my non-green drives in the dedicated cooling bay.  Is this correct?

For some of the previous discussions of drive temps, see the Fans topic, it is scattered throughout the fan discussions.

 

General feeling here I think, is that for longest life, idling temps should be in the 20's to mid 30's, and in heavy use should be 30's to mid 40's.  But everyone has their own opinion.  I believe manufacturer's actually state that operational temps can approach 70, but no one I have read seems to feel that is wise.

Thanks for the reply.  After reading some other threads, it seems that I should be aiming for the 30's and that some of my temps are a bit high.  I'll try to kick the fans up a notch, and maybe remove the dust filters (though my house is really dusty, I would prefer to keep using them).

 

Edit: Actually, after doing a bit of cable rearranging to improve airflow (see proceedure, pics) I have noticed my temps drop 2-5 degrees C, so perhaps that's enough (and I don't need to turn up my fans).  I'll keep an eye on it.

I have the same Antec P180 case with 6 drives currently installed. You migh already know this, but you can very easily install (existing space with screw holes) a 120mm fan in front of the upper HDD cage blowing into the case. For me it made a huge difference since the temps of those drives in the upper cage dropped from ~40 to sub-30 after installing the fan. Lower cage HDD's are around 24-26 idle and ~30 during parity check so now all drives are almost identical temp wise. I'll soon have to add more disks and I'm still looking for well ventilated 3-in-2 backplanes as I have 4 5.25" bays vacant.

 

If you really want the case to be more silent, you should switch the stock Antec Tri-fans to something like Nexus. I use stock coolers but my server is located in a secondary room. To my taste the case is actually quite silent even with stock coolers. I suspect that you could leave the new fan in low setting, so it makes little or no more noise. I doubt that setting the existing fans to high mode would make a big difference for upper cage hdds since the case has multiple air intakes and the intake behind the hdds isn't the easiest route for air.

Very good points, thank you for the input.  I don't have a fan installed in the upper drive bay area, and I seem to remember reading that you have to remove the drive bay to install a fan.  Perhaps that means you remove the bay once, install the fan, then replace the drive bay, but I took it to mean that it was either one or the other - fan or drive bay.  I figured the fan slot was intended for dedicated video card cooling, not for the hard drive bays.  Good to know that's not the case, I may look into that.  For that slot, did you buy another Antec TriCool fan, a Nexus, or something else?

 

I agree with you that increasing the speed of the case's rear fans probably won't help cool the upper drive bays much, though I haven't tried it yet.  Increasing the speed of the fan in the lower bay will probably have more impact, and I expect it won't contribute much noise since it doesn't vent directly out of the case, like the other two fans do.  I may try that soon.

 

I believe my biggest problems with heat were actually with the 4 drives in the lower bay, since they are packed in there pretty close.  However, by reorganizing my cables I have allowed for more airflow and my drive temps in the lower bay are now indistinguishable from the drive temps in the upper bay.  A few of the drives are still running a bit too hot for my liking (45-47 degrees C in an ambient temp of ~30 C), so I'll keep messing with it.

 

I also agree with you that the stock Antec TriCool fans are amazingly quiet on 'low' speed.  Even if I do have to turn them up a bit in the summer, I can deal with the slight noise increase (it will still be quieter than my desktop, which sits very close to the server).  For at least 9 months out of the year, the 'low' speeds seem sufficient.  Therefore, I doubt I'll replace the stock fans, though I will consider adding a fourth fan to the upper drive bay as you recommended.

 

Also, just curious, do you use the dust filters?  I'm considering removing them to see if it lowers drive temps a bit.

 

If you do find a good backplane please let me know as I would like to pick one up as well.  Currently two of my 5.25" bays are occupied by hard drives via 3.5" to 5.25" brackets, but this isn't an optimal solution.

Very good points, thank you for the input.  I don't have a fan installed in the upper drive bay area, and I seem to remember reading that you have to remove the drive bay to install a fan.  Perhaps that means you remove the bay once, install the fan, then replace the drive bay, but I took it to mean that it was either one or the other - fan or drive bay.  I figured the fan slot was intended for dedicated video card cooling, not for the hard drive bays.  Good to know that's not the case, I may look into that.  For that slot, did you buy another Antec TriCool fan, a Nexus, or something else?

You can definetely have both fan and upper drive cage. You actually get very good air flow as the drives are not so close to each other as they are in lower drive cage.

 

I had a spare TriCool fan laying around so I decided to use it. First I tried to install the fan with old rubber grummets but after a while I realised that they had been somehow damaged so I just used screws. You have to remove dust filter during the installation.

 

I agree with you that increasing the speed of the case's rear fans probably won't help cool the upper drive bays much, though I haven't tried it yet.  Increasing the speed of the fan in the lower bay will probably have more impact, and I expect it won't contribute much noise since it doesn't vent directly out of the case, like the other two fans do.  I may try that soon.

 

I believe my biggest problems with heat were actually with the 4 drives in the lower bay, since they are packed in there pretty close.  However, by reorganizing my cables I have allowed for more airflow and my drive temps in the lower bay are now indistinguishable from the drive temps in the upper bay.  A few of the drives are still running a bit too hot for my liking (45-47 degrees C in an ambient temp of ~30 C), so I'll keep messing with it.

The lower chamber is almost fully isolated from the rest of the case; the front fan is blowing air in and the psu fan in the back is blowing it out making a kinda wind tunnel. Thus I assume that the lower fan setting doesn't have an effect on upper cage drive temps.

 

All my drives are Samsung Spinpoint F1 1TB models. Currently we have a bit of a heat wave here in Finland so ambient is around 25 C in the evening (I know, at least it ain't snowing). Drive temps after 15 min of parity check are ~30 C. So there is a huge difference in ambient vs drive temp compared to your system. I think I have the low fan set as high and others medium. You should definetely try a higher setting.

 

Also, just curious, do you use the dust filters?  I'm considering removing them to see if it lowers drive temps a bit.

 

If you do find a good backplane please let me know as I would like to pick one up as well.  Currently two of my 5.25" bays are occupied by hard drives via 3.5" to 5.25" brackets, but this isn't an optimal solution.

I do use the dust filters. I've have owned almost a dozen different computers cases and this accumulates the least amount of dust inside. To my experience if the filters are not completely clogged with dust there is sufficient air flow. I vacuum clean them only occasionally.

 

I have found the following 3in2 back planes available at my local dealer (both around 100eur):

http://www.chieftec.com/sst2131.html

http://www.icydock.com/product/mb453spf.html

The lower chamber is almost fully isolated from the rest of the case; the front fan is blowing air in and the psu fan in the back is blowing it out making a kinda wind tunnel. Thus I assume that the lower fan setting doesn't have an effect on upper cage drive temps.

I understand this, I should have been more clear.  I meant that the lower fan probably has a greater impact on the lower bay drive temps than the upper fans have on the upper bay drive temps, due to the wind tunnel design. 

 

All my drives are Samsung Spinpoint F1 1TB models. Currently we have a bit of a heat wave here in Finland so ambient is around 25 C in the evening (I know, at least it ain't snowing). Drive temps after 15 min of parity check are ~30 C. So there is a huge difference in ambient vs drive temp compared to your system. I think I have the low fan set as high and others medium. You should definetely try a higher setting.

Yeah, big ambient temperature differences there.  It makes it a bit more scary that the drive temps I reported above are during normal operation, not even during the added stress of a parity check!

 

I have found the following 3in2 back planes available at my local dealer (both around 100eur):

http://www.chieftec.com/sst2131.html

http://www.icydock.com/product/mb453spf.html

Thanks for the links.  Those both look nice, but they are a bit pricey.  I guess the hot-swap feature comes with a premium.  unRAID doesn't support hot swap (right?), so I'm guessing you just want to be able to replace and upgrade drives more easily?

I´m looking for easy access but the most important factor is cooling. I don´t know how those backplanes cope with the 80mm fan. If there was a simple 3in2 mounting rack with possibility to install 120mm fan and dust filter in front of drives, it would be a perfect solution. Unfortunately I have never seen such a product. Has anyone else seen anything like that?