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Imac AMD Zen
- Thread starter AsprineTm
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GPU's are worse for encoding because video encoding is a linear task. GPU's excel at what they do through parallel processing. Encoding through a GPU uses a very lossy technique to make the linear task parallel. Its tremendously faster but sacrifices quality, this is why I said for the use of video work.
There are ways to leverage the GPU but in the end the heavy lifting will fall on the CPU. QuickSync greatly aids in this task also, which is an Intel proprietary tech.
Now that doesn't mean AMD can't make (or doesn't already have) their own tech that just needs to be implemented by app devs.
EDIT:
I found this, I havent watched it but I think he'll talk about it.
I want to keep implying I'm talking about dedicated encoding, for the use of video and film thus the highest quality possible. Even programs like Handbrake for encoding your own media. Just don't want someone to get the wrong idea. And I fully acknowledge the GPU can be leveraged for video work and probably even some of the encoding process dependent on the software being used (I think Final Cut utilizes the GPU in various ways for background rendering).
GPU's can integrate dedicated means of encoding. In this case its NVENC per your link. Its mostly used for game streaming. It offloads the work from the CPU so its available for other task (playing games, twitch, etc).
Keep in mind, for it to be as good as a CPU that little portion of the GPU would need to be as powerful. I would say a good comparison is integrated graphics. Integrated graphics can play a game just fine without the help of a dedicated GPU however its no where near as good as even the weakest of dedicated graphics.
There are even a couple graphs in that link (that I don't trust due to their generic nature) that tend to indicate what I'm saying. The PSNR on the "Quality Comparable" is higher on their HQSlow (assuming that means High Quality Slow) indicating its not as good even when comparable. (EDIT: PSNR is Peak Signal to Noise Ratio in dB so lower is worse)
Just find a piece of encoding software that allows you to use the GPU and try for yourself. Not sure if there is anything out there for Mac but I'm sure there is something on the windows side then compare the output files. Just keep in mind if you can make the resulting file as good you can likely make the CPU only render even better. Better = file size vs quality.
I think we are getting way side tracked from the topic of Zen specifically. But to point us back in the right direction, 8 cores would be excellent for video encoding (Cinebench is usually a good indicator since thats essentially what its doing). The TDP of the 1800x is around that of the 7700K (WAY lower then the 6900K which is 140 I believe). So aside from a few proprietary features I think it would awesome for a video editing rig. I can't wait till a reputable source post handbrake times across their entire line up vs intels line up.
Yes, I saw that PSNR graph. But I think Quick Sync does not support 8K lossless, for example.
Kind of a moot point. I think an 8 core Ryzen CPU could overpower a 4 core Intel with software leverage QuickSync for h254. I doubt the same could be said for 8k since you'd likely be encoding in h265 or VP9 which Kaby Lake natively supports.
The only time I tried to encode in h265 was with Handbrake which didnt (and probably still doesn't) have very firm support for. But it added 10+ hours onto the encode time and the resulting file wasnt even remotely worth the time spent.
Also I'm just assuming these things arent built in since Ryzen currently isn't an APU. I could be wrong and our entire discussion is pointless.
Slightly off topic but can you link a Thunderbolt card that compatible with an AMD motherboard. Most everything I find is x99, z87 and z170 etc only. You mentioned earlier about adding Thunderbolt but I'm not finding much if you arent using an Intel chipset. But I also can't find anything specifically saying it won't work, just nothing on cards that list compatible motherboards.
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I believe it does and has for a while. I can't find anything saying otherwise anyway.
I don't care about hardware support for encoding in the CPU. I expect that to be in the GPU, but regarding AMD, I don't know if they are competitive right now in this area, maybe we'll have to check again with Vega.
Some AM3+ motherboard with Thunderbolt were shown at some point, but maybe they were not sold because it seems Intel did not certify them.
So the benchmarks for Ryzen are a mixture, they both win and lose in certain areas compared to Intel's counterparts, granted always for a cheaper price.
I still don't see any reason Apple would swap on a first generation, too much risk for no benefit to consumers at all except a price drop which could come back to bite them if there's any kind of Software compatibility issues or chipset quality issues.
It's good to see Intel getting good competition though, the CPU market has stagnated for too long.
I still don't see any reason Apple would swap on a first generation, too much risk for no benefit to consumers at all except a price drop which could come back to bite them if there's any kind of Software compatibility issues or chipset quality issues.
It's good to see Intel getting good competition though, the CPU market has stagnated for too long.
On macOS, Final Cut Pro X has supported Quick Sync for years. This enables encoding and decoding H264 about 4x faster than purely software methods.
TDP of 1800x and 1700x is lower than the prosumers cpus of intel, but the actual power consumption and heat is on par or even higher according to reviewers. Thats why we will never see these in an iMac. They are very good workstation CPUs but they are almost overclocked to max at factory and need a lot of cooling.
If you want to use these CPUs you better build a machine yourself, thats what I am going to do.
If you want to use these CPUs you better build a machine yourself, thats what I am going to do.
Honestly, dismissing it entirely by "temperature and power" is kinda over-generalization. There is a stock 65W TDP model, the TDP of the chip itself is configurable, and temperature of the top-of-the-line 1800X is more or less on the same level as i7 7700K, which is essentially a higher clocked i7 6700K that is the BTO option of 2015 iMac. It is also possible for Apple to get customised SKUs if it wants to.
Do not draw your conclusions about Ryzen CPUs, yet. The platform is completely immature, there are bugs to be sorted out, and new BIOSes for MoBos are coming each day. This is completely new platform, and software is not ready for it.
Games are not ready yet, presumably because AMD wanted to avoid any leaks, and did not gave out enough CPUs to game developers to work on the game performance pre-release.
Games are not ready yet, presumably because AMD wanted to avoid any leaks, and did not gave out enough CPUs to game developers to work on the game performance pre-release.
Or modify the iMacs cooling system. Granted it would be tough but Apple engineers might be able to come up with something. Remember when the Power Mac G5 was water cooled from Apple? Sure its had leaking issues but an over engineered solution could work.
However I do agree with @Systra72 I think at this point in time it will only be used in workstations. Maybe the future Mac Pro, who knows.....