Windows 10: Why is my high end computer struggling to run any YouTube videos?

I've built a new machine. I've installed Windows 11 pro, new drivers, windows 11 has no new updates- I've updated all I can think of. My hardware is quite beefy:-Asus TRX50 SAGE wifi motherboard-AMD Threadripper 7960x-RTX 4090 ROG Strix-Fast Gen4 and Gen5 SSDs-4x rdimm 96gb each, total 384gb ramThe computer should be having no issues running just about anything, much less youtube videos, and yet it lags when I play anything. The mouse lags pretty moderately, any input is fairly delayed. Once I pause the video, everything returns to normal. What could be the cause of this clear lag? I'm not see

:)

 

Can't get Youtube to show videos in Chrome

I haven't gotteen to this suggestion yet - but, I've shut down half my Extensions and, now, I get the voice of the Youtube videos - but still not the video. Thought this clue might help.

 

Can't get Youtube to show videos in Chrome

Load this checklist video in Edge: (I'm assuming you did at least a few of these steps, since you stated you tried other suggestions earlier) Go through the list of suggestions here to try to repair YouTube for Chrome...

 

Why is my laptop struggling to run high-quality YouTube videos?

My laptop has been a low-end, slow device for the longest time. A few days, I finally decided to upgrade some components. I added another 4 GB RAM (Totaling 8 GB) and installed an SSD. I also installed a fresh Windows 10. The laptop performance has improved drastically except when trying to run high-quality YouTube videos, mainly 1080p or above. It was even worse before but it's still not gone.

However, it's not the typical lagging. My internet is fine. It even shows that the video is loaded way ahead of the point where I'm watching. Yet it lags. But instead of just showing the loading animation and the video pausing, it sometimes slows down the video (FPS drop), or the loading animation comes up and the video becomes black, or it reduces the quality to 144p, or the audio and video desynchronizes for a few seconds.

And as I already mentioned, it's not my internet. It shows that the video is loaded. And I run more than four other devices on the same WIFI, one of them also being a laptop, but they're completely fine.

I'd really appreciate it if someone could help me fix this ASAP. It's been bugging me a lot for the past couple of days. Thanks in advance.