So, a few days ago I noticed that I was having some stuttering issues with Opera Gx. It started hapening after I updated to the latest version. So I uninstalled Opera Gx and installed the previous version. But the issue was still there. Then I noticed what the problem was. I had two tabs that were using around 300% of CPU (acording to the Hot Tabs Killer) (also, those 2 tabs were a couple of livestreams I was watching on Facebook and Twitch) and I had the CPU Limiter turned on at 33% on Gx Control. Turned off the CPU Limiter and there goes the stuttering issue but CPU Usage went from 33% to around 70 or 80% according to Gx Control. On the Task Manager CPU Usage was around 80 to 100% and also I was reaching max temperature on my CPU. (I'm on a laptop so high temperatures are "normal" when I'm playing but it shouldn't be that high when just browsing).

And here is the thing. A couple of weeks ago I was able to have 2 1080p videos and a 1080p livestream playing At The Same Time With the CPU Limiter turned ON at 33% and didn't have any issues at all. So I don't know why all of the sudden Opera Gx seems to be using huge amounts of CPU when playing videos and/or livestreams. Also, on a side note, I openeded 2 livestreams at the same time on Chrome and didn't have any issues so it would seem that the problem is only on Opera Gx. Anyone has any suggestion or idea?

I have an Asus Scar laptop with an Intel Core I7-8750H (6 cores 12 threads) running Windows 10 Home Edition and Opera GX 75.0.3969.255 (64-bit).

@gyrotakashi Thanks for all the input. I tried changing all those things in about://flags/ and you're right, it does help a little bit. What bugs me is why this started happening all of the sudden? A few weeks ago I had no issue at all. And as far as I can see, there are a few other persons with it as well. My guess is that the only real solutions will come only from Opera. We users can't really do much. Anyways, I'm going to leave a few notes in case anyone finds them a good use.

Apparently, when you turn on the CPU Limiter On Opera Gx it actually changes the CPU Affinity so it runs on less cores. I have the Limiter turned On at 33% so Opera Gx uses 4 out 12 cores.

Here's a screenshot from QuickCPU. Can you guess which 4 cores is Opera Gx using while watching a 1080p60FPS stream?

And just to compare, here a screenshot while watching a 1080p60FPS stream but on Chrome.

Quite a difference if you ask me. Also, turning off the limiter on Opera Gx makes the browser use all cores, but then all of them are at above 80% usage which translates into a high CPU Ussage overall plus very high temperatures.

Again @gyrotakashi solutions about changing a few things in the about://flags/ section helped me so others might try it. But it feels as a workaround until the real issue can be found and fixed.

@nandyy I know, I'm using Chrome for watching Twitch or YouTube, otherwise my laptop would just explode for the heat and the high CPU usage. Already tried with Hardware Acceleration on and off and so far nothing. Reinstalled Opera Gx a couple of times and also nothing. And I hace no idea what could be the cause of this problem. Don't know if it would be worth it to file a Bug Report so someone can check it out.

@kurosora I have a similar issue. But in my case, even watching videos makes my CPU go crazy high. Last night I tried to play a little bit while having only one livestream open and my FPS were horrible. Closed the livestream tab and FPS went back to normal. So yeah, there's definitely something going on with Opera Gx and I can assure that it wasn't there before.

So, a few days ago I noticed that I was having some stuttering issues with Opera Gx. It started hapening after I updated to the latest version. So I uninstalled Opera Gx and installed the previous version. But the issue was still there. Then I noticed what the problem was. I had two tabs that were using around 300% of CPU (acording to the Hot Tabs Killer) (also, those 2 tabs were a couple of livestreams I was watching on Facebook and Twitch) and I had the CPU Limiter turned on at 33% on Gx Control. Turned off the CPU Limiter and there goes the stuttering issue but CPU Usage went from 33% to around 70 or 80% according to Gx Control. On the Task Manager CPU Usage was around 80 to 100% and also I was reaching max temperature on my CPU. (I'm on a laptop so high temperatures are "normal" when I'm playing but it shouldn't be that high when just browsing).

And here is the thing. A couple of weeks ago I was able to have 2 1080p videos and a 1080p livestream playing At The Same Time With the CPU Limiter turned ON at 33% and didn't have any issues at all. So I don't know why all of the sudden Opera Gx seems to be using huge amounts of CPU when playing videos and/or livestreams. Also, on a side note, I openeded 2 livestreams at the same time on Chrome and didn't have any issues so it would seem that the problem is only on Opera Gx. Anyone has any suggestion or idea?

I have an Asus Scar laptop with an Intel Core I7-8750H (6 cores 12 threads) running Windows 10 Home Edition and Opera GX 75.0.3969.255 (64-bit).