I do have a cautionary tale about fanless though. I have a fanless 500MHz VIA that acts as my off-site backup server and lives in a friend's apartment.

To start with I didn't have a case fan, just the fanless motherboard a single 3.5 inch drive and the power supply. After having three hard drives die within about a 2.5 year period I took a look at hard drive temperatures.

I found the drive was running at well over 50 degrees C. So I now have two case fans mounted and the latest drive has last two years without complaint.

So don't assume just that your board is fanless that your drives will be happy.

I also have one of those T2 boxes, with a head pipe to make the board fanless, but again I have ended up fitting case fans to get the drive temperatures down.