Friday, November 21st 2025
Seasonic Developing 1,000 W Fanless PSU Rated 80 Plus Titanium
Seasonic is reportedly developing a passively cooled 1,000 W power supply for desktop PCs, according to Cowcotland. This unit is expected to join the PRIME Fanless TX family and might be named the Prime Fanless TX-1000. It is said to have an 80 Plus Titanium efficiency rating and could debut at CES 2026 in Las Vegas. Currently, Seasonic's fanless line tops out at 600 W and 700 W, including several PRIME Fanless TX and PX models, as well as a passively cooled Prime Titan. All these units share a compact ATX footprint of 170 × 150 × 86 mm, are fully modular, and are rated Titanium or Titanium Plus.
Reports suggest the new 1,000 W design would maintain the series efficiency, targeting about 94% at 50% load. It would also feature the same 100,000-hour MTBF and 12-year warranty typical for the family. However, key details remain unknown, such as whether the unit will support ATX 3.x, its connector configuration, and price/availability information. Don't expect it to arrive at the cheaper side since the Prime Fanless TX-700, a 700 W unit, is currently $378 at US retailers like Amazon.
Sources:
Cowcotand, via HardwareLuxx
Reports suggest the new 1,000 W design would maintain the series efficiency, targeting about 94% at 50% load. It would also feature the same 100,000-hour MTBF and 12-year warranty typical for the family. However, key details remain unknown, such as whether the unit will support ATX 3.x, its connector configuration, and price/availability information. Don't expect it to arrive at the cheaper side since the Prime Fanless TX-700, a 700 W unit, is currently $378 at US retailers like Amazon.
21 Comments on Seasonic Developing 1,000 W Fanless PSU Rated 80 Plus Titanium
Then again, I'd imagine you're just about guaranteed to have the longest-life (by specification) components in this PSU.
If Seasonic is giving this thing a 12-year warranty, every component should be (near) 'top shelf' or 'industrial temperature range rated'.
When its efficiency is say 90%, it loses only around 10% of those transformed 1 kW, or around 100 W - there is always a way to cool 100 W passively - of course the airflow of the PC case is essential.
But I agree - passive cooling is just stupid - better take a high-end, silent, low noise 140 mm fan, put it in there and call it a day.
I can sorta see where this kind of PSU is desirable/has a market, though.
A. Anywhere 'the acoustic floor' matters.
B. Extreme applications where dust must be prevented from entry to the chassis; de-rated by use [<500W as a sealed unit?].
My Current Corsair AX850 Titanium which is based on the Seasonic Prime Titanium platform has been the best PSU i've owned and still has 4 years left on its 10 year warranty.
(Personally I'd like no SATA or Molex connectors, because I only use m.2 drives now. This in turn I'd expect would also reduce the needed size of the unit.)
I've been using Seasonic Prime Fanless Titanium 600W since 2018
'Strap a (filtered) P12/P14, etc. on/in the thing, and expect to pass the thing down to your kids :laugh:Not worried. Gotta be a new standard by then.
The entire ATX standard, is not and was not planned-out to accommodate over 1KW of equipment inside the specified enclosure/chassis.
Beyond the organization and structure of the power rails, the mountings and expectant ventilation are insuffcient for >450W+ add in cards and 200W+ CPUs.
New standards have been tried (BTX) in the past but, there's never been such strong motivation (in the consumer market), before.
Though pretty sure components will be very overspecced and that there's been extensive 24/7 torture testing in elevated temperatures.Do you understand how much of heat to get rid that 100W is in the space of PSU without some airflow?
And relying on boosting case cooling to give that airflow kind of defeats the whole point:
Just like PSU is inefficient for cooling the case (as it was planned to do in original ATX layout from time when CPU's tiny heatsink having tiny fan was novelty) case cooling isn't efficient for cooling PSU's inside.
PSU having own fan running even at minimal speed, with no real sound in case of good fan, is simply far more efficient cooling solution.I suspect 80+ Ruby efficiency would be very hard to achieve for ATX PSU and we might not see it outside special uses like server PSUs.
Then again Seasonic discontinued/EOL'ed many of their Titanium PSUs apparently in first half of year if not earlier.
And without replacement/successor untill apparently some time in next year that's just weird long time to have part of flagship range missing.
So maybe Seasonic has been working on something new approaching being ready only now...
Can always dream.
Though more likely it's been just about component availability/production capacity limits and deciding what to prioritize.BTX existed because of Intel's basically failed CPU design decisions leading to heat output blowing up on their face.
Fortunately common sense prevailed then.
Currently using their 700W Fanless PSU.That's even true for active cooled PSU's.
I had a 850W PSU from Seasonic once, and with the fan facing down for cool air from the bottom it kept turning on. When i flipped it around with the fan facing inside of the case i stayed passive at the same loads.
Haven't checked it since the release of original Prime Titanium models with 30ms hold-up time instead of measly 17ms of ATX spec.
(ATX 3.1 is downgrade with poor 12ms requirement, besides leatherjacket's garbage connector...)
I am more of a semi passive kinda guy though.. if I was gonna do it.. just so I am not bound to stock performance.
I would have zero worries about loading this PSU.
If I got a GPU that needed over 300W things might get a bit too noisy, it's the only metric I care about when reading GPU reviews. I'm a quiet PC freak :)
I applaude their engineering, but money better spent elsewhere.
The point is if you need a 1000 watt PSU that means you have a machine that is probably drawing somewhere between 500 - 800 watts under load. That load whatever it is is getting turned into heat in the rest of your system which is going to necessitate active cooling which makes the entire concept of a fanless passive PSU pointless.