Thanks for your answer.
For @ashman70, that is an idea. And yes you are right, I am using an raid5 array
So for the transfer state, I will have 8TB parity hard drive & 8TB hard drive + 3TB hard drive. For sur it will work, but one thing I am afraid of is if one hard drive failed on my synology during the transfer, I loose all my data
For @tdallen, that's more what I have thought. I was presuming that was the case but we never know
And yes it's a pretty powerfull processor.
I planning to run a plex server, have a openelec VM for kodi or something like this, one or two Windows VM, a bluray ripping machine and play with all awesome dockers & plugins. Maybe this Xeon is overkill, but I prefer to be future-proof
Many thanks