Sandy Bridge bug confusion, misc info

[fishfood]

1. What exactly is the Sandy Bridge 23.976 hz bug? ( aka "23.976 fps bug'" or "24p bug" )

2. Does it affect CPUs? Or motherboard chipsets?

3. In what specific conditions does it occur? Do you have to attempt to run your display at a strange 23.976hz refresh, get 24hz instead, AND play a 23.976 fps video? On my current non-SB build, I have had my display adapter set to 60hz for ages and play 23.976 fps videos fine all the time in MPC-HC and VLC.

4. Are B3 revision H67 boards affected? Are Z68 motherboards affected?

5. Does NOT using the integrated graphics on Sandy Bridge CPUs avoid the problem?

6. Is this even worth being concerned about as I'll probably stay at 60hz?

7. Are there any other Sandy Bridge related problems or caveats before I buy one?

 

[Tsumi]

I believe it causes stutters when playing video, and doesn't affect games. It only occurs when playing videos, because the framerate of the video doesn't match up with the GPU, so it will occasionally "skip" a frame.

It's an inherent GPU problem, which affects all Sandy Bridge processors.

I believe modern discrete GPUs do not have this problem.

That's what I gathered on other related posts, not sure if my information is still relevant or correct.

 

[fishfood]

Thanks Tsumi. I have read so much conflicting info that I really hope to hear from more posters as well, no offense.

I'll be using the onboard GPU though, until I can afford better. I will be running at 60hz refresh though, not 24 or 23.976hz.

 

[Forceman]

Thanks Tsumi. I have read so much conflicting info that I really hope to hear from more posters as well, no offense.

I'll be using the onboard GPU though, until I can afford better. I will be running at 60hz refresh though, not 24 or 23.976hz.

I doubt your video refresh rate will have any impact on it, as it is a source encoding frame rate issue for movies that are encoded at 23.976 fps.

 

[Archmage]

If you're looking for more detail, Anandtech's coverage of this issue was quite thorough IIRC.

http://forums.anandtech.com/showthread.php?t=2198726 - It looks like Ivy Bridge will not have fixed the issue entirely, but Intel claims significant reduction in observable stutter.

 

[Tsumi]

Thanks Tsumi. I have read so much conflicting info that I really hope to hear from more posters as well, no offense.

I'll be using the onboard GPU though, until I can afford better. I will be running at 60hz refresh though, not 24 or 23.976hz.

As was said, the fact that you're running at 60 hz doesn't matter. The GPU will still skip over frames because the intervals in the video files doesn't match up with the intervals at which the GPU processes the file.

 

[Ultima99]

Intel should get it right or leave graphics to the big boys that can handle simple video playback...

 

[iconiK]

Intel should get it right or leave graphics to the big boys that can handle simple video playback...

Or maybe people should stop using videos with framerates based on retarded NTSC framerates, which were based on AC frequency.

What's wrong with making videos 25 or even 30 FPS? >.>

 

[Forceman]

Or maybe people should stop using videos with framerates based on retarded NTSC framerates, which were based on AC frequency.

What's wrong with making videos 25 or even 30 FPS? >.>

It's still an arbitrary number - gotta pick something.

 

[anarchyx]

Wow that really sucks, read through all of this and was bummed