1. If I upgrade the motherboard in my current UnRaid server, what is the affect on my current setup? Do I need redo my disk configuration? I have a 16 port raid card and the drives connected to it will remain unchanged, only my on board drive connections will obviously change.

 

2. The 25 device limit in UnRaid pro, is that 25 including cache and parity or 25 plus cache and parity?

 

3. My current UnRaid server is running an older Intel C2D 8400 CPU, if  all my server is doing is acting as a NAS and doing a single thread of Plex every now and then, will a dual core i3 CPU be ok, or should I be considering a quad core i5?

1. If I upgrade the motherboard in my current UnRaid server, what is the affect on my current setup? Do I need redo my disk configuration? I have a 16 port raid card and the drives connected to it will remain unchanged, only my on board drive connections will obviously change.

It should work unchanged. 

 

2. The 25 device limit in UnRaid pro, is that 25 including cache and parity or 25 plus cache and parity?

It includes all drives managed by unRAID (thus includes parity can cache).  With the Pro license then you are allowed additional drives that are not managed by unRAID (in other license types these count against the license limit).

 

3. My current UnRaid server is running an older Intel C2D 8400 CPU, if  all my server is doing is acting as a NAS and doing a single thread of Plex every now and then, will a dual core i3 CPU be ok, or should I be considering a quad core i5?

I suspect you are fine, but I am not a Plex user so that is just a guess.

3. My current UnRaid server is running an older Intel C2D 8400 CPU, if  all my server is doing is acting as a NAS and doing a single thread of Plex every now and then, will a dual core i3 CPU be ok, or should I be considering a quad core i5?

 

Probably, there are some rough guidelines on Plex Support. I went for the i5 in a similar situation, the difference in price over the estimated lifetime of the system wasn't that big in my case. Pretty sure the i3 would have been sufficient.

Thanks that link was helpful, I think a dual core i3 will do the trick.

 

AM