Silverstone SX800-LTI

800W continuous output (850W peak) with 80+ Titanium certification delivers 90% to 94% efficiency across the 10% to 100% load range, genuinely exceptional numbers that exceed what most full-size ATX units achieve, packed into a footprint built specifically for small form factor cases. A single +12V rail rated at 66A reflects a clean, class-leading power delivery design for this form factor.

The 120mm fan, larger than the fans found on standard SFX units and part of what defines the SFX-L format's advantage, uses intelligent RPM control with a minimum 18dBA noise floor during active operation. Below 20% load, the unit switches to fully fanless semi-passive operation, meaning genuinely silent running during typical idle or light desktop use.

100% modular cabling using flexible flat cable arrays is specifically engineered for small form factor case constraints, where standard round cables can be considerably harder to route and tuck away cleanly given the limited internal volume.

All-Japanese capacitors and strict ±3% voltage regulation reflect genuine premium build quality, and a power density of 775W per liter is a real, measurable engineering achievement specifically relevant to the small form factor category, where every cubic centimeter of case volume matters.

Against a standard ATX unit like the Corsair RM850x, covered elsewhere on this site, this Silverstone model delivers comparable wattage in a dramatically smaller footprint specifically built for SFX-L-compatible small form factor cases, at a real price premium reflecting both the Titanium efficiency tier and the engineering required to fit this much capacity into a compact form factor. Within the small form factor category specifically, this remains one of the highest-wattage, highest-efficiency options available, a genuine flagship pick for anyone building a powerful small form factor system rather than compromising on capacity to fit a compact case.

Small form factor builders who refuse to compromise on power capacity. This is specifically engineered to bring near-ATX-flagship wattage into an SFX-L case.

Buyers who want the highest available efficiency tier in a compact form factor. Titanium certification here is a genuine, rare achievement for this category.

Anyone building a powerful ITX-adjacent gaming or workstation system. 800W of Titanium-rated power comfortably covers demanding component pairings in a small case.

Not for standard ATX cases or builds without a genuine small-form-factor size constraint. A standard ATX unit, several covered elsewhere on this site, will be more cost-effective for a case with no space limitation.

Not for the most budget-conscious small form factor builds. Titanium efficiency and this wattage tier carry a real price premium over more modest SFX units.