PCIE gen2 x16 slot and 2 nvme SSDs...

[Laov]

Hello,

 

I'm a new member who just joined the community and built my 1st unraid server. I'm experimenting a bit to make my server better. Please feel free to correct any of my assumptions if they are wrong. I don't require any dire support I'm just curious if what the topic says can be done.

 

I'm running UNRAID on an old mobo.
GA-78LMT-USB3 REV 4.1 (might upgrade eventually if one of my family members decide that they want a PC upgrade).

Primary use case for the server is NAS. It is hosting important family media files. Family videos, pictures and some documents. Before the server we would use external hard drives but manually keeping redundancy over 5-6 drives with ages unknown started to annoy me so I turned an old PC into an unraid server.

 

After finishing my server I decided to add some cache to minimize disk spin ups as this server will mostly sit idle (until I figure out another use case like a security camera ingest station). I have these 2 NVME ssds that were intended as failing external hard disk replacements and a free PCIE gen 2 x16 slot... Thus I chugged a random PCIE x4 to NVME adapter and one SSD worked like a dream... And now I'm wondering if the slot can handle 2 of them for redundancy...

 

I read a bit and it seems that splitting an x16 slot can be done through either self bifurcated card or a motherboard bifurcated card. Correct me if I'm wrong but self bifurcated cards are 100 eu and upwards. The other way is through mobo bifurcated cards which cost ~ 20 eu. I'm 90% sure my mobo does not support it though... Is there such a thing as software bifurcation? I read in a few places that PCIE to NVME adapters become tricky if you want to boot from an adapted SSD otherwise they are straight forward. Could this be the same case for dual slot NVME adapters? I currently don't have one other wise I would have just tested it...

 

100 eu for a self bifurcated card doesn't make much sense for my case. I'd rather spend that money for a mobo x cpu upgrade which would land me NVME slots or at least a few more usable PCIE slots. Now around 20 eu is doable just to state my curiosity for "can this actually work". Any suggestions on how I can cheaply put 2nd NVME ssd's in this setup?

 

And now a post script question as I CBA to make a new topic just to ask if my assumption is correct. As far as I can imagine the main use for a ssd chache is minimizing HDD spin ups, a faster file seek time (at least for the files on it) and perhaps it would help with security camera ingest / compression. 1Gb/s ether net connection should not be able to saturate even a HDD running on Sata 2. Is there any other benefits for an SSD cache that I am unaware off?