SFF standard

[tinyitx]

Sorry for asking a few newbie questions in this forum.
Is 20 litre the 'standard' definition of a SFF case?
Where does this 'standard' come from? Is it simply a general consensus of the community?
And, this 20L is the internal volume (vs external dimensions including the case feet...etc) of a case, correct?

 

[SeñorDonut]

I don't think it's an actual standard, just more of a general consensus. And when I refer to volume, I always mean external volume unless otherwise specified, but maybe I'm doing it wrong.

 

[Runamok81]

General consensus. I think efficient use of space is really what we are about.
Rule of thumb: I'd say anything using full ATX mobos and power supplies is off the table.
mATX is upper limit... mITX with SFX power supply or DC-DC bricks are standard. STX mobo (5x5 inch) and and smaller are rare indeed.

 

[confusis]

20 litres has been defined in Intel design documentation for some time. It is accepted that this is measured externally including all case feet and extensions. Internal volume is just cheating.

SFF Network has taken the above 20L external measurement as our definition for content production.

 

[Runamok81]

Oh, I stand corrected!

 

[SeñorDonut]

General consensus. I think efficient use of space is really what we are about.
Rule of thumb: I'd say anything using full ATX mobos and power supplies is off the table.
mATX is upper limit... mITX with SFX power supply or DC-DC bricks are standard. STX mobo (5x5 inch) and and smaller are rare indeed.

Isn't the Cerberus X 19.5L?

 

[eutholevonik]

Isn't the Cerberus X 19.5L?

I believe that's internal dimensions but I could be wrong. I'm getting ~23.4 liters using the exterior measurements.

 

[ChainedHope]

I always considered 2 things when deciding if something was SFF. If case volume is < 20L its SFF, if its not then space efficiency needs to be about 90%.

An example would be the new 8x mining rid in the build log section. Id consider it SFF because regular setups are usually MUCH larger and in their new designs are even more space efficient.

 

[tinyitx]

I always considered 2 things when deciding if something was SFF. If case volume is < 20L its SFF, if its not then space efficiency needs to be about 90%.

An example would be the new 8x mining rid in the build log section. Id consider it SFF because regular setups are usually MUCH larger and in their new designs are even more space efficient.

Interesting idea you have. But I think it is hard pressed to call a packed 80-litre case (regardless how dense or sparse it is) a small form factor case. Maybe another category named SEF (space efficiency factor) should be used to designate such cases?

 

[VegetableStu]

I always considered 2 things when deciding if something was SFF. If case volume is < 20L its SFF, if its not then space efficiency needs to be about 90%.

An example would be the new 8x mining rid in the build log section. Id consider it SFF because regular setups are usually MUCH larger and in their new designs are even more space efficient.

not sure where i got the 30L number from, but that's the max I feel ATX should be to be roughly SFF. (although there's the argument that ATX is unnecessarily large for most wants)

 

[ChainedHope]

Interesting idea you have. But I think it is hard pressed to call a packed 80-litre case (regardless how dense or sparse it is) a small form factor case. Maybe another category named SEF (space efficiency factor) should be used to designate such cases?

Dunno why but your SEF comment made me think of a mini server farm lol.

The general idea is that if you can make something at a much smaller and denser rate than about 90% of the market, im going to call it SFF. Just because it might be "big" doesn't mean its not small in context.

As an example, a smart car is SFF compared to most other vehicles and vastly smaller than the lifted 4x4 trucks and suvs on the market. Different context, similar principle.