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Does CPU or GPU have more of an effect on video playback

King_V

Illustrious
Ambassador
I suppose there might be multiple answers to this, depending on what site/video source we're talking.

I've generally not had any problems with video playback on YouTube, or with existing MPEG files and such.

However, the other night, I tried to use HBOGo. I was reminded that, oh yeah, they require Adobe Flash player. Ugh. I used to do that on my primary system, but have since stripped it out.

I am using the latest Firefox web browser, 64-bit. I installed Flash, then tried to watch something on HBOGo with my secondary system. Windows 10 Pro, 4GB DDR2 RAM dual channel, Q9550 CPU (4 core, 2.83GHz), and a Radeon HD 4870 video card. Yes, I realize this is aging hardware. Side note, the PCIe x16 slot really is a x8, though I am given to understand that this has only a slight effect on gaming performance.

The system very nearly choked on it.

I went to my son's machine, since he already has Flash on there, Windows 10 Home, 4GB DDR3 single-channel, Haswell Pentium G3220 (3.0 or 3.1 GHz, not sure, 2 cores), and a Radeon R7 250E.

It was slightly choppy at first, but then smoothed out. Occasionally I'd notice very slight hitches here and there, but otherwise, it played reasonably well.


Now, if we go by the hierarchy charts, for GAMING, the Q9550 might have a slight performance edge over the G3220, and the HD 4870 and R7 250E are about neck and neck in performance.


So, is this a matter of:
- the more modern video card having better built-in video decoding?
- the G3220 having a higher clock speed (and/or better overall IPC)?
- something else I am completely missing?

I'm just curious as to where the chokepoint is. I imagine Flash is more burdensome than the typical video encoding used, if I were to guess.
 
Generally speaking, the GPU will have more of an effect. However, it does depend on the software and hardware involved.
Flash certainly has high CPU overhead, and I doubt Flash video is optimised for more than two cores, so the G3220 will probably handle it better.
However, unless HBOGo uses HEVC/x265 or some uncommon video codec, the 4870 should be able to decode it.
 
All, I should also note that the browsers are set to use Hardware Acceleration.

@Zerk - They're both connected through the same router - I have 25Mbps service.

@jakjawagon - that's the odd thing. Neither machine has ever had trouble with YouTube, etc. I had assumed that HEVC or x265 was what YouTube used, but I could be wrong. Given that HBOGo requires Flash, then it's strictly a CPU issue?

(do video cards have hardware decoding for Flash?)