I wanted to replace my aging home server so I took advantage of the great pricing and thread count of the Ryzen cpus. I also wanted some cpu horsepower to enable multi transcodes in Plex, so in looking for a low wattage CPU with lots of threads I started looking.
GENERAL BUILD ADVICE, notes to think about
I got a CaseLabs Mercury S5 on sale for 137 from Microcenter so that limited me to the mATX form factor. The CaseLabs HDD expansion fits in there great, but be advised that is a tight fit. You will need to take the top off of the case and then pull the HDD bracket through the top to make any changes. I put the 2 pressure style Noctua fans in front of the HDD bracket and it keeps them very cool even though only the bottom one actually pushes air directly on the HDDs, temps on those hdds run around 29-30c with ambient around 72f.
The best mobo in that form factor is either the Gigabyte AB350 or the Asus Prime AB350. I went with the Gigabyte and could have easily gone with the Asus if it was on sale. Its still a really close call they are almost identical. The only reason I might go with the Asus over the Gigabyte is that the hwmon.it87 package is updated for the chips on the Asus. If you aren't going to run Linux then you don't have much to worry about. The chips are updated in hwmon on the nightly build for it87, so if you are going to run the newest kernel, its not a bother either. Like I said, its really close. One thing I do prefer on the Gigabyte is the 3 PWM headers in addition to CPU, which I took advantage of.
I put an M.2 sata SSD as a cache drive for UnRaid. Note that it has the M.2 slot, but it only accepts the sata SSD type, correct part is in the list. When the M.2 is present #5 sata is disabled, so it has 6 disks in total capable without expansion cards. Then I am running UnRaid off of a USB attached to the USB3 header near the front which enables 5 drives for data and 1 drive for cache.
I went with UnRaid over FreeNAS because I wanted to slowly expand my total storage. FreeNAS requires you to add dual HDDs each time you want to upgrade. I wanted to add a single 8TB when they went on sale. UnRaid allows this. Its as simple as connecting the drive and starting the array. It also allows for great docker support and VMs. I've been doing a lot of dockers and VMs since this and the cpu/memory absolutely chew everything up.
Even though its not in ear range I wanted to make sure that it was semi-quiet and wanted good quality fans to make sure they pushed air. Over the years the main problems that I've always run into have always been around heat. I've never used Noctua fans, but I must say they are very impressive. Although they are too expensive for what you get, I mean 2.5 fans cost equals the motherboard, which is silly. I chose the NF-P12 fans which are designed for pressure to be right in front of the HDDs, and a NF-S12 to be the rear vent. After its all said and done, it is unbelievably quiet. It is quieter than a 1070 GPU. The loudest things in the entire case are the HDDs and you wont be able to get those any quieter, they are already mainly 5400s.
The AMD chips do not have onboard graphics, so you must have a GPU to be able to use the bios. I wanted a passive graphics card so the fan wouldn't have to run constantly. The best passmark score I could find and it being passive was the new MSI 1030. The benchmark scores are respectable and it is absolutely passive. It works great.
MORE TECHNICAL BUILD ADVICE, notes to think about
I ran KillaWat and got around 60w at idle and at full load 130w. I can probably get this down if I removed the GPU, from what I have found its about 15-20w idle.
Update the bios immediately, F3 has many stability fixes. Also note that after you update the bios, the Virtualization is DISABLED (even though it should be default ENABLED). So make sure you root around and ensure everything is working before you tear your hair out.
If you are hardcore into VMs, you cannot passthru the GPU if its on the top PCIe slot. The IOMMA groups are really lacking for that slot (as of F3 bios, 184.108.40.206 agesa). This will probably improve over time. [EDIT: Situation is unchanged as of F5A bios 9/16/17, 220.127.116.11b agesa)
If you want to use the PWM controllers, temperatures, you need to run the nightly of it87. The IT8733E chips are new and everything is slowly updating kernel wise.
[ 9142.757674] it87: Found IT8733E chip at 0xa40, revision 2 [ 9142.757699] it87: Beeping is supported [ 9142.758124] it87: Found IT8733E chip at 0xa60, revision 3
What a great build. The cpu, mobo, memory are relatively cheap in comparison to what you get. 12 threads in Linux just chew up just about everything you could possibly need.
I run several dockers and its an automatic downloading beast. I run Deluge, Sabnzbd, Jackett, Sonarr, Radarr, Sickbeard, Hydra, Plex Media Server 24/7 and its fantastic. It never hiccups.
I run a Handbrake docker to transcode random videos so they can be read by Plex. Although not technical I usually get around 30fps transcode speeds with fast/very fast settings in Handbrake.
Updated to F5A of the bios. I saw a few more options in the bios, but the IOMMA groups are still not separated properly for the 2nd pcie slot.
three of the orange Sound Harbor sata cables have gone bad. I would randomly get READ DMA EXT errors. The write errors were caused by faulty cables. I've since replaced them with asus sata cables that I did by hand. If you want to make your own colored sata cables, you will need 12mm heat shrink and 10mm pet flex sleeving. Both are found on eBay for cheap.
I stress tested it over 24 hours and the first point of failure was the SSD overheating. I installed a heatsink on the Samsung EVO and it seems to have reduced it by a few degrees.
I replaced the Corsair PSU with a Seasonic. Didn't have any problems with the Corsair, but I just installed a UPS and wanted it all to be the best possible. Someone mentioned my fans were worth more than my PSU, so I took care of it. lol