RX 460 HTPC - Unable to play 4k H.265

[mikemarsh76]

So I've spent countless hours (days) researching this problem, tried different fixes, but I'm not getting anywhere. I recently updated my HTPC in order to maximize my new 4k television, and when I fired up a 4k H.265 movie the picture froze while the audio played on.

My setup is:
Gigabyte GA-F2A88XM-D3HP (FM2+)
AMD Athlon X4 845
MS RX 460 GDDR5 2GB (RX 460 2G OC)
G.SKILL 2x4GB @ 1600
EVGA SuperNOVA 650 G2
Certified 18gbps HDMI cable
Windows 7 Ultimate 64
VLC 2.2.4

My processor usage is spiking 95%+ when attempting to play 4k H.265, and on a side note when playing 4k H.264 saw processor usage in the 40-60% range. This symptom is puzzling, as I thought that the RX 460 was able to decode H.265 10-bit 4K.

Although I enjoy troubleshooting stuff like this on my own, I'm at a point where I've surpassed my expertise. Really looking forward to your feedback!

 

[Sinistercr0c]

What software are you using to play you H.265 content?

EDIT - Sorry just noticed your using VLC...which should work without issue.

 

[why_wolf]

my understanding is VLC has trouble with 4K H.265. Have you checked your settings to make sure hardware decoding / GPU acceleration is turned on?

 

[mikemarsh76]

my understanding is VLC has trouble with 4K H.265. Have you checked your settings to make sure hardware decoding / GPU acceleration is turned on?

Thanks for the response why_wolf. I did navigate to Tools --> Preferences --> Input & Codecs Settings.

Under the Codecs table, there is a selection labeled "Hardware-accelerated decoding". The choices there are:

Automatic
DirectX Video Acceleration (DXVA) 2.0
Disable

After searching about this input, it does look like these choices replaced a previous checkbox for "Use GPU Accelerated Decoding". That choice does not exist anymore.

DirectX Video Acceleration (DXVA) 2.0 did not make a noticeable difference when selected. After searching this term, it appears to be a Microsoft API that allows rendering functions to be offloaded to the GPU.