Running VLC on 8 monitors - Optimization help

[DasHHat]

I am using VLC in my IT shop window display running off 2 GTX 660ti's and an intel G3220.

I was hoping to utilize GPU acceleration to push the 11,000x1024 total split into 4 separate instances of VLC with video wall to enable it split videos between the monitors in pairs.

A test run using lower resolution videos went fine, running 8 different videos on the monitors at once.

However upon attempting to play 720p mp4 footage I quickly hit a CPU bottleneck at 100% usage with a single video using 20%, with the GPU's at just 10% each.

I have tried setting hardware decoding under input/codecs to the DirectX video acceleration but it did not help. Does anybody have any ideas what I can do or what codecs/video formats are best for GPU decoding to take the strain off the CPU.

[If you're interested in seeing what the low resolution test looked like you can find it here: https://goo.gl/photos/gSkEn3Pd9rTD1cKR6 Excuse the band, it was a Victorian evening, hence all the black and white videos!]


Thanks for reading, any advice would be great.