I have an older Intel® Xeon® CPU E3-1230 V2 @ 3.30GHz CPU in my server. I use it mostly for Plex and it is maxed out. At night I have between 8-12 people watching movies and it just can not handle it. I have about 30TB of uncompressed blu-ray rips on the server. My plan is to eventually upgrade the CPU, motherboard and memory. In the meantime I am considering adding a graphics card to keep me going. However I have concerns that the CPU won't be able to keep up with the audio transcoding, which I understand is done by the CPU and not the GPU. If I were add a quadro P1000 or P2000 what could i except? 

You don't really say what you are currently transcoding from and to.  I will assume that you are going from 1080 to 720 or SD.  Either way, I would say that a video card would definitely help you out.  I believe the P1000 is limited, or locked, to the number of streams, whereas the P2000 is unlimited - or limited only to what will fit into the memory.  You shouldn't have any problem with 8-12 concurrent 1080 transcoding streams using the P2000.  Video is much more demanding to transcode than audio so you should absolutely see a difference in performance.  Keep in mind that you will need a plexpass to take advantage of hardware transcoding.

Thanks... I already have a plexpass. Most of the transcoding is from uncompressed original bluray 1080p to compressed 1080p or 1080p to 720p. I don't think the people that use it (friends and family) are able to direct play.

 

Also, my motherboard (https://www.supermicro.com/products/motherboard/Xeon/C202_C204/X9SCL.cfm) has two PCIe x8 slots.. no x16. Based on the info I have gathered from the internet that appears to not be a problem with the P2000.

 

Any other concerns.