Throwing more EMI fuel to the fire, newer GPU ram is now also error-corrected and can lag in performance.
Was watching LinusTechTips today about GPU overclocking (this vid), and...

It's literally, RAM with error-detect-and-retransit, not simple FEC (Forward Error Correction) algorithms of classic ECC memory.
So, yet another error-corrected element in a computer that can also lag. At the tight margins of ultra-high-speed memory that's being pre-overclocked at the factory. Those real tight tolerances.
The complete entire input latency chain, from button-to-photons, necessary has to go through the GPU funnel, so it's relevant to include this factor.
It's not completely inconceivable that we'd see certain specimens of overclocked computers in tempered-glass towers slowing down in realtime as soon as we had a high-EMI device nearby (Such as an old vacuum cleaner or old fridge/drying machine startup nearby behind the wall immediately behind the computer tower). Imagine, overclocked PCs with multiple buses fine-tuned to near its breaking point simultaneously, PCI-Express (error retransmit), GDDRX6 (error retransmit), NVMe (error retransmit), etc, strategically fine-tuned to exactly the breaking point. With all showing ~0.000001% retransmits that could spike to 10%+ retransmits with small EMI sources creating human-visible lag with a nearby old vaccuum cleaner motor or whatnot.
Like an Internet connection suddenly getting 10% packet loss -- except it's your RAM. Your PCI Express. Your NVMe. Trying to retransmit data out of the wazoo. Even if it's nanoseconds, it's lag death by millions of nanoseconds.
<Speculation>
Who knows, later this decade, someone will probably create a viral video about that -- on a computer pushed to its overclocking breaking point (where it becomes suddenly EMI-lag sensitive), like "WATCH THE VACCUUM CLEANER CREATE LAG ON COMPUTER!" or "WATCH MY SMARTPHONE CREATE LAG ON COMPUTER!" whatnot (smartphone in 1-bar reception zone in a phone call or continuous LTE/WiFi-transmit) as they wave the phone towards the computer innards. Perhaps an old electric drill with a spark-generating DC brush motor. Mind you, you'll have to multiple mudane household devices that may nail specific EMI problem frequencies (test quite a few), before you find one that creates weird computer slowdowns. Then create that viral YouTube video and make many industry jaws drop. It'd be funny and sobering at the same time.
P.S. You Youtubers, feel free to give me a shoutout for idea.
</Speculation>
For strong-EMI environments, maybe it is time to buy a full-metal-box computer tower as a "more complete Faraday cage" instead of a temperred glass window, eh?

More error correction layers out of the wazoo.
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