Could Modern PCs Be More Sensitive to EMI/Power Noise? My Old i5 + GTX 1060 Feels Smoother Than a 9800X3D + 4070 Super

[Hyote]

Chiming in because I have the exact opposite experience. Upgraded from a 10850K that was originally paired with a 2070 then a 6900 XT to a 9850X3D with the same GPU. The biggest difference however came from the other parts. My Intel build was all black and had a glass panel case whilst my new build has parts that are all white (some YouTube EMI theory) and a white optic fibre DisplayPort cable. The experience was 1:1, the exact same. I even have a HX1200i now so the power supply theory got debunked for me as well. I'll tell you what made my experience different:
- applying the SCEWIN settings from my guide
- custom Windows with custom kernel drivers
- a sub 100 hns timer resolution (there are guides about going above 0.5 ms for the best sleep delta but the same can be achieved by going below 100 and testing)

I would say I'm an EMI sufferer but overall with high performance in games and these solutions I have a 99% perfect experience. I couldn't even tell the difference between times of day like this.
Even my very old build that had an i5-6600 and a 1060 as well had slight lag, that's when I started tweaking.

[MK92]

I would say I'm an EMI sufferer

No you are not, because the true house wiring / electrical noise problems cannot be improved, fixed, masked or anything else with a simple windows software settings, unless you directly re-program the CPU and MOBO chipsets to remove or optimize error-correcting protocols (but then your PC won't even boot, unless the electricity is 100% perfect)...you have some other problems, or you just think that you "fix" something by fiddling with random irrelevant settings...placebo.

[Hyote]

I would say I'm an EMI sufferer

No you are not, because the true house wiring / electrical noise problems cannot be improved, fixed, masked or anything else with a simple windows software settings, unless you directly re-program the CPU and MOBO chipsets to remove or optimize error-correcting protocols (but then your PC won't even boot, unless the electricity is 100% perfect)...you have some other problems, or you just think that you "fix" something by fiddling with random irrelevant settings...placebo.

My settings are nowhere near the definition of simple. Do you think it's simple to make software that modifies the timer resolution to go below 0.5 ms? Apart from that the other drivers do real work too, such as reverting the garbage 10 MHz QPC timer to true TSC. That's why I used to sell it as a product because I almost sweat blood to make it work. Even now it's unchanged, I have a really positive experience with both a custom install or just a playbook variant I have. So yes, I think you can have EMI and also mask the symptoms as you worded it.

[MK92]

You don't have "emi", you just probably optimized alredy correctly working hardware to work even better, and thats all. You said that you don't notice diff between night and day anymore - so which symptoms exactly did you have during the day when interference is higher, but then it became fine after apllying your fix? If its only "floaty mouse" in shooting games, then this is not EMI problem.

Windows internal timings cannot override mobo/cpu hardcoded error-correcting timings...this is like saying that you fixed your clogged toilet by optimizing water smart meter settings, and not by plumbing.

I'm not saying you didnt improve your system with tweaks, but what I'm saying is that your problems are 100% not electrical if you managed to actually feel the difference by doing just software tweaks.

[Hyote]

You don't have "emi", you just probably optimized alredy correctly working hardware to work even better, and thats all. You said that you don't notice diff between night and day anymore - so which symptoms exactly did you have during the day when interference is higher, but then it became fine after apllying your fix? If its only "floaty mouse" in shooting games, then this is not EMI problem.

Windows internal timings cannot override mobo/cpu hardcoded error-correcting timings...this is like saying that you fixed your clogged toilet by optimizing water smart meter settings, and not by plumbing.

I'm not saying you didnt improve your system with tweaks, but what I'm saying is that your problems are 100% not electrical if you managed to actually feel the difference by doing just software tweaks.

That's true, I had nothing apart from floaty mouse but that was gone when I
1. installed a fresh OS
2. played early in the morning or at dawn

As I progressed with tweaking these differences faded.