Hi there,

I’m currently running Unraid version 6.12.6. My server has 8 data drives and a single parity drive, each has a capacity of 12Tb giving me a total storage space of 96Tb. I have the HDDs housed in 2 Norco SS-500 5-in-3 cages.

Here (in New Zealand), it’s currently the end of winter, and slowly turning into spring. I try to run a parity check every month, and it takes from 20-25 hours to run. The last few months I’ve noticed I’m getting warning messages in the Unraid web interface that the drives are getting hot. The last parity check I ran last week and I could see that some of the drives were reaching 50 degrees Celsius (about 122 degrees Fahrenheit). Some of the drives were a little better (47-49 degrees), but all were over 40 degrees.

If I’m seeing temperatures this high in late winter, I don’t like the idea of how high those temperatures will reach during summer. While I have a little time – time to put some thought into finding a solution.

The server is sitting in a small office off of our garage, where my wife works. A while back I swapped out the stock fans at the back of the Norco units with quieter fans (as my wife was getting annoyed with the server fan noise). While the new fans did the trick noise-wise, I now have the problem that the new fans don’t seem to be providing sufficient cooling. The fans on the back of the Norco units aren’t the easiest things to replace either. My son had to help me change the fans as I’m a tetraplegic. One of the 4 plastic pillars the fans are supposed to be fitted onto broke last time. You can see the story of how the fans are fitted at the bottom of this review page…

http://greenleaf-technology.com/new-norco-ss-500-5-in-3-drive-cage-review/

I’m happy enough to move the server to a different part of the garage to keep my wife happy, but I need to find a better cooling solution, and I’m looking for any solutions you might have. The current fans are (I think) Noctua NF-A8 FLX 12V 2000RPM fans as shown here…

https://quietpc.co.nz/casefans?sort=price_desc&instock=selected&case_fan_size=80&case_fan_thickness=25&voltage=12%20

Any suggestions for fans with the same 4-pin connector, and same size (80mm x 25mm) would be appreciated, although I’m not opposed to any left-field suggestions either. The important thing is that whatever the solution is – it MUST keep the hard drives adequately cool at all times, but especially during long-term use (like a parity check).

For those of you living in hotter climates, how are you keeping your drives cool? Thanks for any and all suggestions!

5 hours ago, Roscoe62 said:

For those of you living in hotter climates, how are you keeping your drives cool?

Typically you just need some airflow around the drives, enough to try and keep them under 45C

Have you cleaned out the case? Best way to to use compressed air (cans or hand held blower). Make sure you do it some place where the resulting dust and dirt storm does upset your wife!

Make sure that the fans are not having their speed controlled by some other temperature measurement.

Make sure that your fan setup is pulling all the cooling air in from the front of the drive housing(s) and exiting from the back of the case. (No fan behind the drive housing should ever be blowing air in the server case. All fans must be setup to blow air out! Close off any opening in the back portion of the server case that will allow air to leak in without going across the drives. Remember that electronics have far higher temperature specs than the HDs.

You may have to opt for noisier case fans (not the ones on the drive housing(s) after that horror story to change out the originals!) and position the server where you can have some sound isolation around it.

OK thanks. This seems to me to be the best course of action...

1. Shut down the server and move it onto a desk for easier access

2. Remove the side panels and (with everything still connected) start the server and manually/physically check the fans at the back of each of the Norco units to ensure they're oriented correctly - i.e. - pulling air from the server front, and blowing the exhaust air into the case

3. If the Norco fans are not oriented correctly, power down the server, and re-orient the fans. If they're oriented correctly, continue.

4. Power down the server and remove any/all dust from within the case

5. Examine the back of the case - check any rear fans & ensure they are oriented correctly - i.e. pulling hot air OUT of the case. If the server doesn't have any rear case fans (I don't remember whether it does or not), buy some and install them (ensuring to orient them correctly).

Does this sound reasonable? I'm really hoping the Norco fans are oriented correctly - I don't fancy doing surgery on them again...but I have to check.

Edited October 22, 2025Oct 22 by Roscoe62

OK, it took longer than expected to get around to all of this, but finally it's done, and I've learnt a few things...

1. When the case was open, I cleaned out all the dust I could see - in the case, and around the drive cages (especially around the HDD air intake grills). There was some dust there, but it didn't seem excessive.

2. The fans on both drive cages are correctly aligned - pulling air from in front of the case through the drive cage, and expelling the airflow into the case.

3. There is ONE 120mm fan on the rear of the case, and it is also oriented correctly - to pull air from inside the case and exhaust it out the back of the case.

4. I also noticed some potential issues, and might need some help in finding the best solution to resolve them

Problem 1 - there are a number of entry points on the rear of the computer case. I imagine these will greatly diminish the efficiency/effectiveness of the rear fan. I have (I think) 3 PCI Expansion slot covers missing, I might be able to source some PCI slot covers from a shop that sells computer parts (maybe).

Problem 2 - The original aluminium I/O shield that came with the motherboard is missing. I think the chances of getting a matching I/O shield for this motherboard are slim to none and, even if I could find one, I'd have to uninstall the motherboard to fit it. I'm very open to other solutions!

Problem 3 - There is a spot on the top of the case to install a small fan (80mm I think). There is a fan there already, but the power cables for it have been cut, so the fan is useless.

So - I've ordered a pair of 4 pin 12V fans 2000rpm - one to replace the rear fan that's already there, and a second fan to mount on the rear of the case just below the first fan. The case has the space for that but it's currently been sealed with some kind of foam. I will remove the foam, and set the 2nd fan to also exhaust air out the case rear. Any thoughts you might have in solving the other problems I've listed, I would be very appreciative to hear!

12 minutes ago, Roscoe62 said:

Problem 1 - there are a number of entry points on the rear of the computer case. I imagine these will greatly diminish the efficiency/effectiveness of the rear fan. I have (I think) 3 PCI Expansion slot covers missing, I might be able to source some PCI slot covers from a shop that sells computer parts (maybe).

I have used PVC Electrical Tape to seal these slots in the past.

14 minutes ago, Roscoe62 said:

Problem 3 - There is a spot on the top of the case to install a small fan (80mm I think). There is a fan there already, but the power cables for it have been cut, so the fan is useless.

Replace that fan and put it to use.

15 minutes ago, Roscoe62 said:

Problem 2 - The original aluminium I/O shield that came with the motherboard is missing. I think the chances of getting a matching I/O shield for this motherboard are slim to none and, even if I could find one, I'd have to uninstall the motherboard to fit it. I'm very open to other solutions!

This is a tough one. A sheet of soft form could be cut to block most of the opening. Again, PVC tape could augment the form and help secure it in place.

FWIW, fans that are designed to pull air through the small gaps in the drive bays are usually (not always) loud. High CFM fans does not mean that they can pull air through small gaps. And quiet fans (usually lower CFM) are even worse. Fans you want for small gaps have high static pressure. And the two don't go hand in hand always.

I think your 2000rpm fans for the cases are too slow to suck in enough air through the small gaps between the disks.

You should replace them with faster ones (that of course will be louder too, but not that much if you stick to nocturna or companies like be-quiet).

Also the small fan on top of the case is essential!

Hot air goes UP, it does not matter if your slots are open or the IO shield is missing, the hot air from the disks will never get there. It will be stuck at the top back of the cage and if it cannot get out there, there will be blocking thermal zone. Your front fans wont be able to suck in fresh cool air because of this block

Fix that fan or just pull it out to allow wider escape.

The other obvious help would be to use only every second slot in the cages leaving wider gaps for the air. But its clear nobody buys a 5 x cage to use only 3 slots out of it.

But even then you could sometimes can help by more intelligently plugging in the disks.

If you have SSDs or 2.5" drives, plug them between the 3.5" ones. This also will wider the gap for the air.

Thank you all for all your suggestions! So many great ideas...

I found that my Amazon order for the 2 2000rpm Noctua fans still hadn't shipped, so I cancelled the order and found a local firm that were selling Noctua's "industrial" fan solution - basically they can go up to 3000rpm, and they're a bit louder...so I ordered 2 of those, and from another firm I found an 80mm Noctua fan that spins at 2200rpm, which would be ideal for the case top fan.

When they arrive, hopefully later this coming week, my son & I will fit them, and use PVC electrical tape to seal the open PCI expansion slot cover holes, and probably the open I/O shield hole as well - making sure not to cover the I/O ports we actually use (basically just the 2 network port slots).

I've got a feeling that's going to improve the short-medium term issues very nicely. We'll also have to move the server out of my wife's office, but I'm okay with doing that as I'd rather have the server run louder, but cooler.

Finally, as a longer term solution, I'm going to keep an eye out for a third "5-in-3" drive cage and install that as well. That should allow me to install 3 of my 9 drives in each cage, leaving 2 nice big slots in each cage (and allowing none of the drives to be next to any other) allowing the cage fans to do a much better job of sucking air past the drives.

I'll post back once the new fans have been fitted and I've had a chance to see how that affects the drive temps.

Thanks again!

OK...so I used PVC tape to close the holes in the rear of the case. I fitted a new 80mm fan at the top of the case, and installed 2 new 120mm 3000rpm fans in the rear of the case. I've also relocated the server so it's no longer in my wife's office.

Generally, the HDD temperatures are much better, although we're still not in summer yet.

However, one thing is very annoying. The fans inside the case are all connected to fan headers on the motherboard - a Supermicro X10SRi-F. It seems that the fans are constantly in a "cycle-up, slow-down" loop which repeats constantly. Honestly, I think I'd rather have the fans running at a constant speed because the constant speed-up, slow-down cycle is maddening having to listen to it for very long, but I've gone through the motherboard manual and I can't find any way to over-ride this behavior. The manual mentions some way of monitoring the fans "using the IPMI interface" but - even spending some time reading through the manual - I can't find anything specific.

If you can think of a way to over-ride this maddening fan behavior (whether using a tool, app, plug-in or docker item in UnRAID, or something different altogether - I'm all ears!

2 hours ago, Roscoe62 said:

(whether using a tool, app, plug-in or docker item in UnRAID, or something different altogether - I'm all ears!

https://www.amazon.com/Gavemi-Molex-Adapter-Cooling-Splitter/dp/B0CG2X3DFZ/?th=1

Maybe a manual controller

https://a.co/d/1fJdVM4

Edit:. Adding this clever one

https://a.co/d/fpA9gWs

Edited November 17, 2025Nov 17 by Veah

Fan-tastic suggestions guys! (Pun FULLY intended). Order placed! I didn't really know enough of how this might fit into the server solution - thanks very much for drawing a couple of pictures for me. Much appreciated!