Nvidia NVENC Quadro P5000 vs Tesla M40

[BaconFeet 2]

To make things interesting, we've been debating back and forth between a Quadro P5000 16gb and the Tesla M40 24gb to use in our upcoming server. 

While, I'd normally just go with the higher GPU ram one (M40), we've noticed some lacking transcodes codecs with the older architecture and looking for an opinion from users that might have some experience with these cards. 

 

P5000 4k supported encodes

- H.265 (HEVC) 4K YUV 4:2:0

- H.265 (HEVC) 4K YUV 4:4:4

- H.265 (HEVC) 4K Lossless

- H.265 (HEVC) 8k

 

M40 4k supported encodes

- H.265 (HEVC) 4K YUV 4:2:0

 

Both cards fully support 1080p transcodes and is only really a question of if we would really need the full spectrum of 4k encoding with Emby. 

They both cost *roughly* the same from our sources. In your opinion, would it be wise to go with the P5000 as it's a newer architecture or would we benefit more from the GPU ram the M40 has to allow more concurrent streams?