Just saw this thread and wanted to jump in with a slightly different take. While those premium brands are great, I honestly think you are hitting diminishing returns once you start looking at Platinum units or those high-tier Seasonic price tags. You can save a decent chunk of cash without sacrificing silence if you look at the actual fan curve data instead of just the brand name. I would actually suggest looking at the ADATA XPG Core Reactor 750W 80 Plus Gold or the MSI MPG A750G PCIE5 750W 80 Plus Gold Fully Modular. Both are top-tier on the technical tier lists but often go for 20 or 30 dollars less than the Corsair equivalent. Tbh, the money you save there is better spent on higher-end case fans. For a 3070 and a 7700X, you wont be pushing the PSU hard enough to make the efficiency difference between Gold and Platinum matter for noise anyway.

Adding my two cents here... if you really want to prioritize safety and long-term reliability alongside silence, I would definitely look into the Seasonic PRIME TX-750 80+ Titanium 750W. Its pretty pricey, but the Titanium efficiency means it generates very little waste heat, so the fan stays off way longer than on Gold units. Plus, that 12-year warranty is basically the best in the industry, which gives me a lot of peace of mind. Another solid option that is usually super quiet is the EVGA SuperNova 750 P6 80 Plus Platinum 750W. It uses a really high-end platform and the fan curve is tuned specifically for low noise. Just make sure whatever you get has a physical Eco mode switch on the back so you can actually toggle the semi-passive behavior. Honestly, its worth spending the extra bit for a high-tier unit if youre keeping this build for a long time.

TL;DR: Higher price or efficiency doesnt always mean better acoustics. I totally agree with the point about the diminishing returns. Honestly, its been pretty disappointing to see some of these top-tier brands coasting on their reputation while their newer batches have cheaper fan controllers. I have had issues with some newer Seasonic units where the fan profile was way more aggressive than older models or the Corsair equivalent, which is a letdown when you are paying a premium. To help narrow this down, are you looking for a unit that stays passive even under a 300-400W gaming load, or do you just care about silence while browsing? Also, how much space do you actually have in your case for a longer PSU? Some of those quiet platforms are pretty long and dont fit well in compact builds.

i totally feel you on the jet engine psu thing, it ruins the vibe of a nice build. honestly the Corsair RM750x 750W 80 Plus Gold Fully Modular is popular for a reason. i have used it in my last two builds and the fan almost never spins up during normal work or watching videos. when it does finally kick in during a gaming session, it is basically a whisper. if you want to avoid potential coil whine, maybe check out the be quiet! Pure Power 12 M 750W 80 Plus Gold. it is super efficient and stayed dead silent in the build i did for my brother last year. i found it to be a bit more budget friendly while still giving that premium silent performance. basically either of these will be a massive upgrade over your old one.

Agree with the previous post, but id argue the Cybenetics noise certifications are way more useful than 80 Plus for your needs. Quick question tho, what case are you using? Some shrouds basically choke the intake, which forces the fan to spin up sooner than it should. Also, do you have a strict budget or are you willing to pay a premium for a noise-optimized platform?