Intel's lack of support for industry standard 23.976 Hz output

[CCarn1]

According to Anandtech, Intel said it would fix 23.976 Hz output in Sandy Bridge. That never happened.

According to Anandtech again, Intel said it would fix 23.976 Hz output in Ivy Bridge. That also never happened.

What is 23.976 Hz? Basically, blu-rays will play at the frequency of 23. 976 Hz. Your graphics card needs to output at 1080p at 23.976 Hz to get proper smooth playback. Without proper support from Intel for 23.976 Hz, you will get a frame drop (roughly every 4 minutes with Ivy Bridge).

AMD/nVidia seem to do better than Intel with support for 23.976 Hz. The problem is, if you wish to build a low power, quiet HTPC for playback of movies and you choose a Intel CPU with Intel HD Graphics, you will get frame drops.

When is Intel going to address this issue? I want a Intel HTPC. I don't want to have an external graphics card.

At the moment, if you are lucky - you can set your refresh rate to 23 Hz and it will output near 23.9 but that will still create a frame drop every 4 minutes.

For the uninitiated, 23.976 Hz is for displaying movies, not for your desktop. On your desktop, use 50 Hz or 60 Hz.

[ROBERT_U_Intel]

Hi

Could you please provide me with information on your system? Make, model, BIOS rev.

Thanks

[RMitr1]

Well, since you asked,

I have open ticket (8000556452/8000555097 ) numbers on this, and this is part of the mail I sent to support, including a short summary of the recent history of this 'issue' on intel platforms. From my current understanding and those of others, this is a BIOS issue, which is why I originally posted in that discussion area (see below)

Hi Adrian,

thanks for taking the time.

To summarize: the issue states that 23p display refresh rates are not achievable on the DH77EB board, although they are, in fact, achievable on other boards, including Intel and non-Intel boards with Series-7 chipset.

According to Intel (over a year ago) this capability requires specific support not only from the graphics driver, but especially from the chipset, which is why the BIOS needs to contain appropriate support for it.

So to reproduce, From 2 boards running Windows 7, both with latest BIOS and identical up to date drivers, and either a SB or IB CPU, the DH77EB will not be able set display resolution to say, 1920x1080@23HZ, whereas the DH77DF will. Instead the DH77EB will set refresh rate to 24Hz and the DH77DF (and others) will achieve 23.973 (or so).

In the Intel support community this issue has been last reported in this thread:

/thread/32120 http://communities.intel.com/thread/32120

here's a short history:

01/02/2011 Sandy bridge review with problematic 23p (needs UAC disabled):

http://www.missingremote.com/review/intel-sandy-bridge-core-i5-2500k-and-dh67bl-motherboard http://www.missingremote.com/review/intel-sandy-bridge-core-i5-2500k-and-dh67bl-motherboard

6/26/2011 no more UAC disabling required:

http://www.missingremote.com/news/2011-07-26/24p-works-intel-sandy-bridge-uac-enabled http://www.missingremote.com/news/2011-07-26/24p-works-intel-sandy-bridge-uac-enabled

Things seemed resolved…

At this time the community (kind of) agreed that,

• It has to do with the chipset rather than the processor
• It won't get any better on Series 6 (Sandy Bridge)
• Rumors (fed by Intel reps at e.g. IDF) started that Ivy Bridge will do things a lot better

Enter Ivy Bridge:

4/23/2012 missing remote reviews that 23p is about as good as in Sandy bridge, but not better:

http://www.missingremote.com/review/intel-core-i7-3770k-ivy-bridge-cpu-and-dz77ga-70k-motherboard http://www.missingremote.com/review/intel-core-i7-3770k-ivy-bridge-cpu-and-dz77ga-70k-motherboard

Cheers,

[RMitr1]

As a side note:

I strongly vote to legally _banish_ any HD content that is artificially crippled from the original 24,000 or 30,000 or 60,000 to anything else.

Movies, IMHO are anyway recorded at 24.000Hz only to be crippled artificially on BDs with 23.976.

I understand the compatibilty issue with analog TVs, but who, in his right mind, has the equipment to play BDs and is then using a display device ONLY CAPABLE of 23.976 Hz?

That being said, it's not Intel's fault that the content providers are doing this.

Cheers,

[idata]

Has there been any update on this issue? Considering bying a new HTPC setup (DH77EB/3770T)...but having 2nd thoughts with this 23p issue.

[Jx7]

Still no update from Intel, but you must know that there are many People who doesn't see this bug.

[RMitr1]

I had an open ticket with INtel on this issue. After some initial email passing back and forth on how to see this, it seems to have silently died away.

I have given up hope at least for the dh77eb.

BTW, the so-called 'industry standard' 23p for HD content should be banished. There is no such content, it's just artificially distorted.

[Jx7]

Same here, last Answer war from December 31th:

"We are currently investigating the issue. I will come back to you as soon as I will get an answer from our engineering department, but it could be anything from a few days to a few weeks. Thanks for your patience. "