[sf-lug] "Stick PC" and other SFF computers

[Rick Moen]

To recap, Ken wondered about suitability of a Intel Compute Stick
(https://en.wikipedia.org/wiki/Intel_Compute_Stick, discontinued 2020)
to host a mailing list serve.  It's a fair question and _mostly_ OK 
-- except for being badly handicapped for storage.

It's an example of "Stick PC", a fascinating ultra-small,
ultra-low-power complete computer, made possible by flash media, VLSI 
chipsets, extremely versatile ports like HDMI, and extremely
power-thrifty CPUs (Intel Atom, ARM).

All other things being equal, the smaller the Small Form Factor (SFF),
the better, as long as the generated heat can be
radiated/convected/conducted away well enough.  IMO, Stick PC, though, 
is too mimimal for a reliable server.  "Stick PC" isn't a formal spec,
just a general size and shape.  You get something barely bigger than a
USB stick and about the same shape.  You can plug it directly into the
HDMI port of a monitor, for video output.  Often, power gets supplied it 
via a tiny USB On-The-Go port.  There may be a USB 2.0 port (w/microUSB
connector), and a microSD slot.  And that's it.

THat's not terrible.  You could even have a pair of external SSDs
RAID1-mirrored and connected to the USB (via a hub?).  

But, honestly, what problem are you trying to solve by going so tiny and
cramped?  I know rent in SF is high, but is this because of living in a
closet?

But, point is, going for SFF but not _that_ tiny opens up possibilities
that matter.

One way to discuss this is to talk about standard motherboard sizes,
which _are_ formally defined.  Let's talk about some -- and, for
comparison's sake, the industr-standard ATX form factor for commodity PC
motherboards is 9.6" × 12".


Pico-ITX (3.9' × 2.8")
--------
https://en.wikipedia.org/wiki/Pico-ITX

Pretty darned small.  You get a selection of ports, but, e.g., only one
SATA port, not two (so no RAID1-mirroring, not without an optional
daughterboard).  You can have a real computer with it, like this one:
http://dathsgarage.dk/retro-computer-collection/computers/others/via-artigo-a1000-pico-itx/
As one of the pictures points out, the whole computer is about the size
of a classic half-height CD-ROM drive.

I respect these.  I just think it's good for a server, including a home
server, to be able to have mirrored, high-speed, highly reliable mass
storage.  Without an exotic daughterboard and probably a bigger case,
you'll not be getting that.


Nano-ITX (4.7" × 4.7")
--------
https://en.wikipedia.org/wiki/Nano-ITX

More tempting.  VIA's EPIA N motherboard is an example.  Still only one
SATA connector, but now you also get a mini-PCI slot.  I think these
might be gone from the market, though?  I mean, mini-PCI in 2023?
And a VGA port?


Mini-ITX (6.7" × 6.7")
--------
https://en.wikipedia.org/wiki/Mini-ITX

I still think this is the sweet spot.  The system's big enough to
dissipate heat well, you get a PCI Express slot (sometimes two slots
using riser cards), and the box might have enough room and connectors
for two SSDs.  Kick-ass.

I have sitting in a cabinet a couple of spare mini-ITX-type SFF
computers made by Zotac, which I consider just the thing for many home
and small server uses.  _And_, if you avoid having an overpowered (e.g.,
gamer) CPU, maybe you can run the box fanless, thus silent, low-heat,
and ultra-low-power.


Mini-ATX (5.9" x 5.9")
--------
https://en.wikipedia.org/wiki/Mini_ATX
https://www.pctechguide.com/motherboards/atx-form-factor

As the description says, just a scaled-down variant of ATX (created by
Intel in 1996), always with a low-power "mobile" CPU.  I'll frankly
admit I just haven't seen this, much.  I think they are or were mostly
used for mini-tower systems.


microATX (9.6" x 9.6")
--------
https://en.wikipedia.org/wiki/MicroATX

Another Intel effort (1997) at slightly scaling down ATX, about 25%
shorter in one dimension.  One advantage is that it's backward compatible
with ATX, as in, you can mount it in your sprawling ATX box and
everything is in the right place.  A microATX board will take a maximum
of four PCI-Express expansion boards vs. ATX's seven, but, honestly, how
many do you need?  Rarely would you need more than two, and often only
one or zero, if you plan right.




So, with that survey, let's get back to:  What's the goal?  Yes,
generically it's true that the smaller and more power-sipping the
system, the lower your power bill and the less heat output.  (Also, 
the cooler your equipment runs, the longer it'll last.)  _But_, when
you run the numbers on power-usage/expense, you see that diminishing
returns sets in.

Back in 2013, when I was picking replacement server hardware, I strongly
considered jumping ship from x86 to ARM -- Raspberry Pi or something
else -- and power-consumption / heat was one major argument.  But 
you lose a _lot_ (not discussed here) in making that CPU-arch choice,
and the power consumption of a modern system based on a properly
selected x86_64 CPU with SSDs is actually pretty tiny.




My 2013-era CompuLab Intense PC:
7.5" x 6.3" x 1.6" case, passively cooled with massive fins
1.4GHz 3rd generation Celeron CPU:   CPU Thermal Design Power (TDP) is 17W (max under load)
2x SO-DIMM 204-pin DDR3 SDRAM (max 16GB)
2x internal SATA, 2x eSATA
HDMI and DisplayPort (but it's a server, so who cares?)
2x GbE LAN (and other stuff)
Lots of USB2, and a pair of USB3 ports.
Expansion:  Half-size mini-PCIe socket, _and_ full-size mini-PCIe/mSATA socket

Did not come with mass storage, which I bought separately and attached 
externally.  But, not counting those two SSDs, total power consumption
normally is about 12-15W for the CompuLab as a whole.  The difference in
PG&E charges between the CompuLab and something even tinier and
thriftier is, well, IMO not worth the trouble.

(CompuLab's IntensePC was also available with an Intel Core i7 or i5, as
in the review cited below, but I deliberately did _not_ want that, but
rather the cooler-running, power-thriftier Celeron.)


Here's a picture of one -- banana not included:
https://www.anandtech.com/show/6908/compulab-intensepc-system-review-fanless-ivy-bridge

If you want one with an i5 CPU, used, it's yours for $200 (8GB RAM, 1TB
intternal HD):  https://www.ebay.com/itm/166184161534