power supply - What PSU is usually used in mini-ITX cases/chassis?
2014-07
Subaru Tashiro
The mini-ITX computer will be a general use computer. Not a dedicated HTPC or Home server.
In general use mini-ITX cases, what PSU form factor is usually used? I understand that some case manufacturers provide custom built PSU to fit their case but I prefer to get the ones that use a PSU that follows standard form factors in case a replacement is needed.
For example, what PSU fits into general purpose cases by Lian Li?
Am I to assume that smaller PSU form factors also affect the possible maximum output?
RedGrittyBrick
Wikipedia says
The Mini-ITX standard does not define a standard for the power supply ...
Which means size and layout of PSU depends only on the case.
... though it makes some suggestions of possible options. Conventionally Mini-ITX boards use a 20- or 24-pin "original ATX" power connector. This is usually connected to a DC-DC converter board which in turn is connected to an external power adapter. Generally both the power adapter and the DC-DC board are supplied with the case.
An Intel document suggests
Provided the very different needs of the platforms that fit in the small desktop form category, this specification does not attempt to define a standard for the power supply to match with the Mini-ITX motherboard specification. Instead it recommends that manufacturers consider using a:
- SFX, TFX or FlexATX are available power supply form factor for chassis greater than 5 liters
- External power adapter for chassis less than 5 liters
ninety
Most Lian Li mini-ITX uses standard ATX (PC-Q03, Q07, Q11, etc.) or SFX (PC-Q02, TU100).
The two popular SFX PSU that I know of both top out at 450W http://www.fspgroupusa.com/fsp45060ghs85r/p/858.html http://www.silverstonetek.com/product.php?pid=342 So I think it's safe to assume maximum output will be somewhat limited compared to standard ATX PSUs. That said, if you are using a mini-ITX case, chances are 450W will be enough.
Questioner
I want it to perform good enough as a multimedia machine. Should I get one that is fan cooled or passively cooled? I think I want one with an HDMI port.
What chipset should I look for?
Jeff Shattock
I agree with an Ion chipset, there's really no competition in the quiet/ITX space. I've got one of these powering a secondary HTPC for my bedroom. It has a Celeron 430 35W chip in it, and it runs good and quiet. HD playback is no problem, once I got a codec that uses the hardware decoder instead of trying to shove it through the CPU.
My original thought was to go with the Atom 330 version of this board, but what I've seen about it lead me to believe that it would be too sluggish when using the VMC interface. 4 l-cores or not, its still an in-order architecture. If silence is more important to you, there are some Atom Zotac boards that are passively cooled, and have a power brick instead of a normal PSU.
William Hilsum
If you want a really small system, look for a machine based on Nvidia ION - basically, it has a Atom CPU and can do 1080p output whilst keeping electricity usage low.
I have not seen many machines recently that are passively cooled, but a lot of the newer Atom boards have low noise fans.
geocoin
+1 for an ion as a multimedia machine. low power (both CPU and Wattage) but with a graphics chipset that can hadnle FULL 1080p HD.
some even come with an HDMI port.
If you want a nice easy answer, some pre built ion nettops exist such as the Acer revo, or asus ionstar