Completely passively cooled power supplies are absolutely a thing, but it's rare that you will find one that can deal with any graphics card up to, and including something so beefy as an Nvidia RTX 4080. Cooler Master has got your back with the X Silent 750W PSU it's been showing off at Computex this week.
The smart X Silent PSU in 750W trim has no fans at all and relies entirely on the passive cooling capability of the finned chassis and a copper baseplate with flat heatpipes helping dissipate the heavy thermals such a power supply will generate under load.
Almost two sides of the PSU case itself are given over to acting as an external heatsink, and I guess that's designed to be on the bottom of your PC case. Which is probably going to get rather toasty itself.
It's a proper modular ATX 3.0 design PSU, and that means you get a specific 12VHPWR connection to power that big ol' Nvidia RTX 40-series GPU you covet. The connections also include a USB connection for your motherboard so you can hook into Cooler Master's own software utility to monitor temps and power load of the supply itself.
I've seen 600W fanless Seasonic PSUs in the past, and Cooler Master's own semi-passive designs (you're either passive or not, right?), but not something with this sort of wattage available. That's a positive boon for those of us hankering for a high-powered silent gaming PC build.
But if you're after something quiet that can cope with the rigours of something even more powerful, such as the RTX 4090 in all its thirsty glory, then Cooler Master is also offering the X Silent PSUs in 1350W trim, too.
Pick your jaw up off the floor, though, because this version isn't fanless. It comes with an extra ARGB fan so it can at least look pretty, even if it can't claim to actually be silent.