Which build would be better?

[Alcsi69]

Hey,

So I want to build a mediaserver basically. The heaviest usage would be 1x 4k playback without transcoding, and 3 1080p -> 1080p/720p transcode. 

My original thought was a used office PC. For instance an Optiplex 5040 with an i5 6500 + 16 GB RAM and a couple of 4 TB HDDs, plus a dedicated GPU, like a P400 or something like that.
My other idea would be the same x number of 4 TB HDDs, a dedicated GPU and an X99 build. 

I assume there wouldn't really be a lot of difference because I'd use the dGPU for transcoding right?

[Fate]

If you buy dedicated CPU I would suggest an small Intel ARC like (310) should be better than a p400.

[Alcsi69]

I found out that I could also get away with a 10th+ gen intel cpu with it's dedicated gpu as well. I think these 2 options (i5 6500 office PC + A310, 10th gen intel igpu build) would actually cost roughly the same, but power consumption would be better with the igpu option.