Intel's Haswell - An HTPC Perspective: Media Playback, 4K and QuickSync Evaluatedby Ganesh T S on June 2, 2013 8:15 PM EST
4K for the Masses
After our experience with Trinity and Ivy Bridge builds for HTPC purposes, we had reached the conclusion that a discrete GPU was necessary only if advanced rendering algorithms (using madVR's resource intensive scaling algorithms) or 4K support was necessary. In fact, the 4K media player supplied by Sony along with their $25K 84" 4K TV was a Dell XPS desktop PC with a AMD graphics card's HDMI output providing the 4K signal to the TV. Ivy Bridge obtained 4K display support last October, but not over the HDMI port (which is the only way to get 4K content on supported TVs).
The good news is that Haswell's 4K over HDMI works well, in a limited sort of way. In our first experiment, we connected our build to a Sony XBR-84X900 84" 4K LED TV. The full set of supported 4K resolutions (4096x2160 @ 23 Hz and 24 Hz, as well as 3840x2160 @ 23 Hz, 24 Hz, 25 Hz, 29 Hz and 30 Hz) was driven without issues.
4K H.264 decode using DXVA2 Native and QuickSync modes in LAV Video Decoder works without issues (this works well in Ivy Bridge too, just that Ivy Bridge didn't have the ability to output 4K over HDMI or any other single video link). Using madVR with 4K is out of the question (even with DXVA2 scaling), but EVR and EVR-CP both work without dropping any frames.
Now, for the bad news: If you are hoping to drive the ~$1300 Seiki Digital SE50UY04 50" 4K TV (the cheapest 4K TV in the market right now), I would suggest some caution. Our build tried to drive a 3840x2160 @ 30 Hz resolution to the Seiki TV on boot, but the HDMI link never got locked (the display would keep flickering on and off). The frequency of locking was inversely proportional to the HDMI cable length. The NVIDIA GT 640s that we tested in the same setup with the same cables and TV managed to drive the 4K Quad FHD resolutions without problems. We were able to recreate the situation with multiple Seiki units.
At this juncture, we are not sure whether this is an issue with the ASRock Z87E-ITX board in particular or a problem for all Haswell boards. Intel suggested that the HDMI level shifter used by ASRock might not be up to the mark for 4K output, but that doesn't explain why the output to the Sony 84" TV worked without issues. In short, if you have a Seiki 4K TV and want to use a PC to drive that, we would suggest using a NVIDIA GT 640 or greater / AMD 7750 or greater for now. We will update this section as and when we reach closure on the issue with ASRock / Intel.