[sf-lug] build-a-box project report

Rick Moen rick at linuxmafia.com
Tue Sep 12 13:53:21 PDT 2006


Quoting jim stockford (jim at well.com):

> the motherboard seems not to fit the case, so we built it on the
> workbench.
>
> the motherboard presents four prongs for power to which the power
> supply can't mate.

Well, the manual's your friend.  It's available online here (though
presumably you also had a dead-tree copy):
ftp://dlsvr03.asus.com/pub/ASUS/mb/socket775/P5P800%20SE/e2196_p5p800se.pdf

Your reference to the "four prongs" presumably refers to the square
four-prong socket in the corner.  You _do_ need to connect that 4-pin
one, but also the one set in about two inches from the middle of the
motherboard's rear panel, that has two rows of twelve pins each (24 pins
total).  

Any ATX12V 2.0  PSU _should_ include cables and plugs
for both the 24-pin thin connector and the 4-pin square one.  If your
PSU lacked one of those, then it wasn't a real ATX12V 2.0 PSU, but
rather an old one not usable on PCI Express motherboards.

My SWAG (silly wild-assed guess) is that they accidentally gave you a
slightly antique PSU -- e.g., an old pre-P4/Athlon64 original-ATX
PSU that used 20-pin power connectors and lacked the auxiliary 12V
feed from that extra 4-pin pug.  http://en.wikipedia.org/wiki/ATX

The PSU should be rated for at least 350W, for this model.

It shouldn't be a challenge to fit this motherboard into a _modern_
case:  It's barely less deep than the bog-standard ATX size (which is 
305 mm x 244 mm, aka 12" x 9.6"), has six screw-holes in the usual
places, and should fit into basically anything -- and, in that regard,
I'm amazed they found a case that _didn't_ work.


> to get interleaved RAM memory, do we put the 1GB RAM sticks into the
> two blue sockets or into a single pair of one blue and one black
> socket?

Blue DIMM sockets first (channel zero), then black DIMM sockets (channel
one).  This is detailed in the manual.


> ...(with new, better case, per Rick Moen's comments, that has more
> fans, per Nathan's comments) and afterward we can take it apart to see
> how it's done by the pros.

More fans _can_ and often does mean more noise, especially where people
use tiny fans with cruddy sleeve bearings spinning really quickly so as
to compensate for their size.  Which is unfortunately the norm, and
you're not going to get anything better unless you take a more active
role in your hardware.

All other things being equal, a case with only a couple of
_large_-diameter (and thus slower) fans with good ball-bearing sets is
preferable.  And don't forget the PSU and CPU fans (if any) -- and
sometimes one on the video card (if any).  Those are noise and vibration
sources, too.

Get to know hardware.  You'll learn that some cases and fans are just
designed and built better.  Just telling a vendor "Get me a good one" is
no substitute, and doesn't accomplish anything useful.  In fact, their
response is generally just to pick the next-more-expensive unit off
the shelf, something heavier, noiser, with garish neon lighting to
better appeal to gamer kiddies with more money than brains.

> a note about grounding straps: some use 'em, some don't. I'm in the
> use 'em crowd, tho' i occasionally step out.

Static-electricity damage to chips tends to be cumulative and silent.  
You _will_ damage chips, transistors, diodes, etc., if you don't take
precautions, though you won't realise you're doing it at the time.

> these same some recommend wearing a grounding strap that's connected
> not to just any old piece of metal but to earth ground (the round hole
> in an electrical receptacle).

You want to be on the same electrical potential as the equipment you're
working on, and that should ideally be consensus ground level.  But you
can't just assume that the "ground" connector of an electrical outlet is
grounded; all too many are not.

> Julie at Actnet says bring it back, they'll put it together 

If it were I, *I* wouldn't do that.  I'd say "Please swap out this PSU
and case for ones that _work_ with an ASUS P5P800 SE".  And then I'd
_read the motherboard manual_ thoroughly, make sure I now _really_ have 
all the required parts, and try again.

BTW:  Personally, I prefer retailers who pay attention and don't sell me
incompatible components.





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