YouTube is becoming more and more difficult to watch on old platforms. The aging AVC/H.264 video codec has been quietly supplanted by the more efficient VP9 and AV1 algorithms. It seems that the only way to get an AVC stream these days is to enforce it with a browser plug-in (or use an outdated browser that doesn't support VP9/AV1)
While offering higher visual quality, these new codecs put higher demands on the system. CPUs made in the last decade should have enough grunt to handle them on their own, especially with a low bitrate. For example, my maxed out AM3+ rig from 2012, with an FX-8300 at 4.5 GHz, can do VP9 4K60 without any assistance from the GPU.
But what about older retro systems? I decided to find out just that, putting the slowest 64-bit desktop CPUs from Intel and AMD to the test. The 2.53 GHz Celeron D 326 (Prescott/LGA775) represented Intel, while the oc'd 1.86 GHz Sempron 2500+ (Palermo/s754) fought for AMD. Released in 2004, both processors are 1c/1t. The two systems are equipped with the same 2 GB of DDR1-400 in single channel and a similarly performing HDD. They are running Win7 Home Premium 64-bit and the latest Firefox 115.7 ESR.
With only the CPU doing the video decode, neither system was able to provide a smooth YouTube viewing experience at the lowest resolution of 144p. Adding a Radeon HD2400 Pro, a bottom of the barrel card from 2007 with basic AVC/H.264 hardware acceleration allowed the Sempron to play back 360p streams with very little hitching. The Intel CPU, even though 15% faster according to CPU-Z, still couldn't do even 144p.
So, what if all video decoding could be offloaded to the GPU?
The problem is that the AV1 decoder has only been included on the two most recent generations of video cards, starting with the Radeon RX 6000 and Nvidia GeForce 30 series. While I have two such cards, neither would physically fit on the mATX motherboard of my retro rigs because of their backplate. Also, both are in use in my other systems, and I wasn't willing to tear them apart.
I considered buying a dedicated card for the experiment, but even the cheapest ones with AV1 support, the RX6600 and the RTX3050, are about $250 here (inc. tax). The Intel Arc A310 at $90 makes more sense, but it requires Win10 and Resizable Bar, so a much newer system. And the driver wouldn't probably play nice with my antiquated components. VP9 hardware decode, on the other hand, has been supported since Maxwell on Nvidia cards, and so I got a GT1030 GDDR5 to test my assumptions. This is the weakest Pascal GPU, a slot powered card with a TDP of 30W and full VP9 and AVC/H.264 support.
Amazingly, the Intel system still couldn't manage 144p videos, even with the GPU doing all the decoding!
And it wasn't just the streaming performance, the poor old Celeron simply cannot handle the YouTube back-end. A single page takes several minutes to load and when it finally does, it is completely unresponsive. Sadly, the slowest 64-bit offering from Intel is no longer good for YouTube.
But on the Sempron system the GT1030 allowed me to play back VP9 streams in 480p30 quality with only minimal stutter
My next step will be to find out what it takes in terms of CPU power for a 1080p YT experience. Posting this from the system above!
