Building a new PC... Recommend specs for FAST video playback/seeking?

[Gameshow Host]

After 13 years, the time has come for me to build a new PC. H.265 is painfully slow when seeking, and 4K goes out of synch.

After years of suffering slow video playback, I want a super-fast video machine that lets me instantly skip/jump to different points in the video without any delay! Ideally I'd also like to be future-proof for higher definition than 4k.

Does anyone have any hardware recommendations? (I want AMD not Intel.)

[usually_quiet]

Wait for AMD to release their Socket AM5 desktop APUs later this year.

[Gameshow Host]

Wait for AMD to release their Socket AM5 desktop APUs later this year.

Thanks for the tip! Is this expected to be some big quantum leap for AMD CPUs? Couldn't I just get something from last year, which will be cheaper and therefore I can get a higher spec equivalent?

Also... do you think the CPU is the main factor in video performance then? Not GPU or RAM?

[usually_quiet]

Wait for AMD to release their Socket AM5 desktop APUs later this year.

Thanks for the tip! Is this expected to be some big quantum leap for AMD CPUs? Couldn't I just get something from last year, which will be cheaper and therefore I can get a higher spec equivalent?

Also... do you think the CPU is the main factor in video performance then? Not GPU or RAM?

VP9 Profile 2 and AV1 are both currently used by popular streaming services for 4K HDR content. However, since AV1 is an open-source format, it is expected to replace older formats now used for streaming UHD HDR content by most streaming services in the future.

The new Socket AM5 APU graphics can decode VP9 Profile 2 and AV1 as well as HEVC. The older Ryzen APU graphics can decode HEVC but not AV1. I don't know which of the older APUs, if any, can decode VP9 Profile 2. The currently available discrete graphics cards that can decode AV1 are expensive. It is hard to predict if any cheap ones will be released given the recent improvements in processor graphics capabilities.

Of course, HEVC can be played smoothly using just software decoding given a sufficiently powerful CPU but decoding with processor graphics works quite well these days.

[Gameshow Host]

VP9 Profile 2 and AV1 are both currently used by popular streaming services for 4K HDR content. However, since AV1 is an open-source format, it is expected to replace older formats now used for streaming UHD HDR content by most streaming services in the future.

Thanks for the answer, I'm very glad I asked - I hadn't even heard of AV1 (I read it as "AVI" at first). I also had no idea that CPU hardware decoding existed! That should speed things up, plus save us having to download and install codec packs!

So from what I can tell from a bit of searching, AV1 seems awesome, and the way things are going, so it would be great to hold back for an AMD chip which supports it. However, I really don't have a huge budget, so for now I think I'll get a nice fast Ryzen, maybe from last year, and rely on software decoding!

Any thoughts on GPU or RAM for fast video playback?

[usually_quiet]

Any thoughts on GPU or RAM for fast video playback?

Sorry. I can't offer any advice in those areas.

I have been using an Intel processor's iGPU for graphics since 2014. FWIW I was given a laptop for Christmas with Windows 11, an Intel® Core™ i5-1155G7 and 8GB of memory. The GPU decodes HEVC, VP9 Profile 2 and AV1 video at 4K resolution. The Movies and TV app or VLC can display 4K video on the laptop's 1080p screen with tone-mapping to simulate HDR10. The Movies and TV app often plays video more smoothly.

As far as RAM goes, the most I have installed on any PC is 16 GB.

[Gameshow Host]

Thanks friend, that is all very helpful information

[jagabo]

I also had no idea that CPU hardware decoding existed! That should speed things up, plus save us having to download and install codec packs!

I don't think you understand. CPU decoding is what requires the installation of codecs (or a program that has them built in).

<edit>
Or maybe I misunderstood you. The GPU built into many modern CPUs includes a hardware decoders. But with a powerful CPU software decoding can be faster than the iGPU decoding. Of course, if you are encoding with the CPU having the iGPU do the decoding can increase the overall throughput.

And, of course, all this requires that the software you are using supports those features.
</edit>



Playing video is much different from editing video. To play a 24 fps video smoothly all the player has to do is decode 24 frames per second. If you are sitting at frame 249 of a 250 frame GOP in an editor, and move one frame backward, the decoder may have to go back to the previous keyframe and decode all 248 frames up to the requested frame. If the decoder can only decompress 24 frames per second that might take over 10 seconds. Then if you move one frame back again it will take another 10 seconds. You want a much faster decoder for editing.

[Gameshow Host]

You want a much faster decoder for editing.

As I said in my OP, I'm looking for a machine that can seek quickly. It's rare that I actually "watch" videos - I'm usually jumping back and forward to find certain points, skipping through a video 10 seconds at a time, or going back/forward 1 frame at a time. I do editing as well, but the main thing I need is a machine that can SEEK quickly.

I find it very irritating waiting for the computer to respond when seeking/jumping through a 4K or HEVC video. If possible, I'd like the seek times to be well under a second. But what sort of CPU is needed for that?

[Cornucopia]

Seeking is easy with lots of computers if you just convert to an intra-frame-based intermediate first.


Scott

[jagabo]

One thing I've found is a lot of decoders run single or double threaded. With those having more than 2 cores doesn't help with seeking. I have an 8 core, 16 thread processor (i9 9900K) and VirtualDub uses only one thread to decode 4K 10-bit HDR VP9. With160 frame GOPs it can take as long as 5 seconds to seek. LSMASHVideoSource() in AviSynth appears to run with two threads and seeks about twice as fast with the same file. I don't ahve any of the big NLE programs so I can't give you comparisons of those.

[sum_guy]

For seek buy as much computer as you can possibly afford. Go big!

[Gameshow Host]

Thanks for the info, folks! Interesting note about cores!

Seek speed will matter most in PotPlayer, as that's my default player. I've used it for many years and love it.

[jagabo]

Using Potplayer210318 without "jump to keyframe" with the aforementioned 4K HDR VP9 video, the slowest seek was about 1/2 second, usually much shorter. With "jump to keyframe" enabled it was always essentially instantaneous.

[sophisticles]

@OP:

Since you want AMD, I would look at this:

https://www.microcenter.com/product/639743/amd-ryzen-7-5700g-cezanne-38ghz-8-core-am4-...ooler-included

[jagabo]

If money isn't a problem go for the 5950x and a Nvidia RTX graphics card.

[Gameshow Host]

Awesome recommendations! Thanks! It's been so long since I bought a CPU/GPU that I really had no idea where to begin. The 5950x is beyond my budget at the moment sadly, but still an informative recommendation.

Using Potplayer210318 without "jump to keyframe" with the aforementioned 4K HDR VP9 video, the slowest seek was about 1/2 second, usually much shorter. With "jump to keyframe" enabled it was always essentially instantaneous.

Very helpful info, thanks!