Seasonic is seemingly planning another passively-cooled PSU for desktop PCs, but this time boasting a considerable 1,000W capacity. According to Cowcotland, which was present at the company’s showroom, this model will join the brand’s Prime Fanless TX lineup and will carry an 80 Plus Titanium efficiency rating. Assuming this model maintains a similar design to its predecessors, we can expect an overall efficiency between 91% and 93%, depending on the load level.
This model will be joining the 600W and 700W Prime Fanless TX PSUs, probably rocking a 100,000-hour MTBF and 12-year warranty. Like its siblings, the new Prime Fanless TX-1000 is set to use large heatsinks and a very open mesh frame to optimise heat dissipation and make up for the missing fan. Both existing units share a compact 170mm x 150mm x 86mm footprint, so we assume the 1,000W will follow suit.
To put this into perspective, since the launch of its first 400W X-series fanless PSUs back in 2010, Seasonic has only boosted wattage by an extra 300W, reaching 700W on its highest-capacity Prime Fanless TX model in 2020. This time, it took it just about five years to add another 300W to the mix, announced by this 1,000W unit.
It is unclear however if this model will feature the brand’s Optisink technology debuted with the Focus GX series, which improves thermal conductivity by eightfold and thus boosts MOSFET cooling. A handy feature to have on a fanless PSU, no doubt. The same goes for OptiGuard, Seasonic’s advanced 12V-2×6 monitoring and protection technology showcased at Computex 2025. What is sure is that all upcoming PSUs, including the Fanless TX-1000, will be bundled with a colour-coded 12V-2×6 power cable, allowing you to verify if the cable is properly seated at a glance.
Technically, you can get a similar result by going for the brand’s massive Prime PX 2,200W model which can operate in fanless mode up to around 40% load, but the price may not be the same. Better yet, you could wait for the 3,200W model and its six 12V-2×6 connectors, scheduled for next June, and get around 1,280W of fanless power.
Either way, you will have to put down a hefty sum as I believe the Prime Fanless TX-1000 won’t be cheap. Considering the Prime Fanless TX-700’s £230 price tag, the 1,000W unit will probably retail for £300 or so. We should get more information around CES 2026.
