It’s an interesting initiative, given that there’s no widely adopted standard for what constitutes a small form factor setup. This is in contrast to form factors like ATX, Extended ATX (E-ATX), micro-ATX, mini-ATX, and other less widely known variants (anyone remember BTX?). So if you’re building a compact gaming PC, it takes a bit more research to ensure that all the parts will fit.
Of course, this is also a self-serving standard for NVIDIA, as it’s not pushing guidelines for AMD Radeon or Intel Arc graphics cards. In other words, it’s not a universal standard, though there’s nothing to stop AMD or Intel from promoting the same or similar requirements, if they so choose.
Maximum dimensions check in at 151mm long by 304mm high by 50mm deep (2.5-slot), or around 5.9 inches by 11.97 inches by 1.97 inches. Additionally, the allotted height must take into account space for a power cable. There are a whole bunch of custom graphics cards from several of NVIDIA’s add-in board (AIB) partners that already meet the spec, as outlined above.
Qualifying cases must have 154.55mm (~6.08 inches) of clearance from the motherboard or riser PCB to the case panel (whether the GPU is in a vertical or horizontal orientation), 312mm (~12.28 inches) in length including the graphics card and extender (if applicable), and 50mm (~1.97 inches) in depth, which again is big enough for a 2.5-slot graphics card.
Likewise, several GeForce SFF-ready cases are available now, including models from ASUS, Cooler Master, Corsair, Fractal Design, MSI, NZXT, Silverstone, and several others.