Upgrade time? Looking for suggestions

[bisk]

With US Black Friday and the general Christmas Shopping Season quickly approaching, I thought it might be a good idea to start looking at my options to replace some of the components in my aging 7 year old unRAID NAS.  I am in Canada, but we do see some pretty decent sales here as well.  Here’s what I’m currently running

750 Watt Antec Power Supply

Rosewill RSV-L4500 chassis

CPU - Intel Core i7 3770

Mobo - P8H77-V LE (6 SATA connectors)

RAM - 4 x 8GB DDR3

2 x IBM M1015 SAS Controllers - one card is using 2 x “SFF-8087 to 4 SATA connectors” cables connect 8 internal SATA drives and the other card is using 2 x “SFF-8087 to SFF-8088” cables to connect to a 2U Supermicro DAS for an additional 12 drives

PCI Express SATA controller (only because I didn’t have enough SATA connections for the 15 internal drives)

 

My main use for the server is to host Plex.  I usually have 3 or 4 people streaming remotely (transcodes) and 1-2 streaming locally to an Apple TV, Shield TV or Roku (usually direct play).  I also run a single Win10 VM that I use when I’m away from home or need to do something that I can’t on my Mac or iPad.  The Rosewill chassis 15 drive bays are all full and I’ve got 5 or so drives in the 12 bay Supermicro DAS.  I would love to be able to add a GPU so that I can do hardware transcoding in Plex.  I think my biggest fear at this time is that either the CPU or motherboard will die and that would require replacing the CPU, motherboard and RAM, so I think that would be what I’m looking to replace in the immediate future since the other components could be replaced as onesie twosie.  Anything that can be done to reduce the number of SATA and SAS controllers would probably be a good idea as well.  I'm considering AMD based on the lower prices, but would also consider Intel.  I'd like to keep my budget around $500 CAD for this project if possible.