I've decided to combine my NAS and HTPC into one computer. My current HTPC is running AMD Athlon 5350 (Kabini) on the Asrock AM1B-ITX motherboard with 8GB of RAM, so the idea is to take all disks from NAS (rest of the hardware is very old) and connect them to Asrock. From what I've read my hardware is capable of virtualization, so I would want to run one VM for LibreElec. AFAIK I can't passthrough an integrated R3, so I would need a separate graphic card for Kodi and here comes my question: can you recommend me a graphic card (preferably with passive cooling) that could be easily passedthrough into VM?

How about something using the Radeon HD6450, made by the likes of Sapphire or Asus, like this? They are quite cheap and passively cooled. Bear in mind that although the Asrock AM1B-ITX looks as though it has a x16 PCIe slot only four lanes are populated with contacts, though the card will still work.

 

I've used that same combination of APU and motherboard several times for various projects recently, but not for unRAID. The extra two SATA ports (not provided by the MSI and Asus Socket AM1 motherboards) are useful.

So... I bought the graphic card (btw thank you John_M for your recommendation) and put everything together, just to find out, that my system supports only AMD-V not AMD-Vi. Due to this I'm going to change the rest of my hardware. I want low power consumption, quite system, that will work as NAS with one VM - LibreElec. I've decided on following parts:

 

MB - ASRock B150M-HDV (Socket 1151)

CPU - Pentium G4400 Skylake

RAM - Corsair ValueSelect 4GB DDR4 2133MHz CL15

 

Since I'm putting everything into a 2U case, I'll need power supply that has a fan in the rear, no at the bottom. I've decided on this:

 

Chieftec PSF-400B 400W

 

Could you please confirm, that this will work as expected, so I won't make another mistake?

The Pentium G4400 is a 3,662 Passmark CPU with 2 cores, non-hyperthreaded.  It is VT-x and VT-d capable and so is that motherboard, but I think you're really at the rock bottom of what might work for a VM with hardware passthrough.  I don't have personal experience with this setup, but if it were me I'd spend some time in the VM Engine (KVM) forum looking at the hardware setups other people are using for hardware passthrough.

Based on your config there I'd say it's capable of what you're currently asking of it but not much more. I'd be inclined to bump ram to 8GB regardless.

Ok, so I put everything together and my current setup looks like this:

 

mobo: ASRock B150M-HDV

cpu: Intel Pentium G4400, 3.3GHz with a stock cooler

gpu: Sapphire Radeon HD6450 1GB GDDR3

ram: Corsair Value Select 4GB DDR4 2133MHz CL15

hdd: 3* WD Red - 2TB, 5400rpm (one used as a parity), 1*Samsung hd501LJ - 500GB, 7200 rpm (used as a cache to store VM files)

case: Gembird 19CC ATX 19"/2U (this case comes with two 80mm fans on the front which are connected to a molex so they run all the time at the maximum speed and are very loud - must be replaced)

psu: Chieftec PSF-400B 400W (85% Bronze)

 

Everything is working fine, I tried LibreElec and OpenPHT as VM and Plex in Docker. I made some power consumption tests and here are the results:

1. System power down but plugged into wall - 1,1 W

2. System in S3 sleep mode - 2 W

3. System idle all drives spun down - 34 W

4. System idle all drives spun up - 49 W

5. Parity check in progress (cache drive spun up) - 52 W

6. Parity check in progress (cache drive spun down) - 46 W

7. Max power consumption (Plex with 100% cpu usage all drives spun up) - 65 W

 

I'll replace those fans in the case with ones that are powered from the motherboard and I'll see if it has any impact on power consumption.