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Old December 17th 08, 10:01 AM posted to alt.comp.hardware.pc-homebuilt
poachedeggs
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Default pc transplant - Compaq EN to new case & psu (possible?)

On Dec 17, 4:24*am, Paul wrote:
poachedeggs wrote:
While installing Linux Mint 2.2 on an old Compaq EN SFF 886mhz tonight
the power supply blew. *I don't know anything about building pcs and I
wondered if I could get a case with psu built in and just move the
Compaq in. *The spec is good enough for what it was going to be used
for and don't have the loot to build from scratch or buy new.


A new 120 v psu would be more than I paid for the pc and eBay has no
used ones at present. *When I look at cases with psus the voltage
seems way above 120v - has the standard changed since 1999 or am I
misreading something?


My other option was to move the hard drive (20gb), floppy drive, DVD-
Rom drive, USB card, modem and RAM (2 x 256 mb ram SODIMM 133 mhz into
another 'used' case & motherboard etc, but I'd prefer the first option
as it'd be a semi-new computer. *I suppose it's mostly about whether
the motherboard will fit or something? *Anyway, pardon any naivety.
Any thoughts appreciated.


Is the RAM I've got too old for new motherboards?


Thanks.


It could be similar to the picture at the top of this web page. Power
supply is 120W.

http://h18000.www1.hp.com/products/q.../10653_na.html

(Watts = Volts x Amps, Volts being a constant level
offered by the wall socket, Watts being the variable amount of power
drawn at that voltage. Modern power supplies might span 350W to 1200W,
but the power actually drawn is less than the rating. The 350W is a
*max* and not a constant drain. You can draw up to 350W, and the supply
will be loafing along if you only draw 120W from it. The power consumed
by the PC, changes depending on what it is doing. So a 350W supply can
power a 120W max PC - they both work at 120V, but the 350W supply has a
higher maximum it can handle. There is obviously more to it than this,
but without any concrete info to go on, I cannot say more at this point.)

* Volts *^- - - - - - - - - +
* * * * *| * * * * * * * * *| * * * * Area inside the box is "Watts"
* * * * *| * * * * * * * * * * * * * *Amps increases when the PC is busy.
* * * * *| * * * * * * * * *| * * * * Amps decreases when the PC is idle.
* * * * *| * * * * * * * * * * * * * *The power supply is rated according
* * * *120V * * * * * * * * | -- * * to the maximum power in "Watts" that
* * * *A.C. * * * * * * * * * * * * * it can convert without overheating.
* * * * *| * * * * * * * * *|
* * * * *|
* * * * *| * * * * * * * * *|
* * * * *v
* * * * *---------------------------------------------- *Amps

* * * * * ---- variable, more when PC is busy ---

As near as I can tell, this is an example of a 120W power supply. Too
bad I cannot make out anything on the label. Small form factor power
supplies like this, could have any number of small variations in dimensions,
protrusions and the like. (If you look in the dm/ folder, there are
a couple more examples of Flex supplies.)

http://www.seasonic.com/dm/Flex%20AT...e%20PFC%29.jpg

The card cage on your computer uses an expansion assembly. That means
there could be one connector on the motherboard, and an assembly plugs
onto that. The assembly holds PCI cards, for things like network cards,
modem cards, sound cards or whatever. That is a different scheme and
method than modern computers, and that means trouble when repackaging
your computer. Can the computer be run without the expansion ? Yes,
but some very important functions could be lost, so just throwing that
part away may not be practical.

Now, when you move that motherboard into a standard computer case, you're
going to need a way to hold the expansion assembly secure. The most
common kinds of ATX computer cases would not work.

Perhaps the packaging concept you could use, is the "sheet of plywood"
approach. That would involve purchasing spacers the same size as the
standoffs underneath the motherboard, some kind of screws and the
like, so that the motherboard could be fastened to some plywood.
Next, some small angle iron pieces might be used to hold the
expansion assembly in place. The result is an open concept
computer. (You'd only do this, if you couldn't find a used
case similar to the one you've got.)

I don't know of a way to determine whether the power supply has a
standard pinout. At 120W, it may be possible that all the motherboard
power is handled through one connector. (Hard drives and the like
still need their connectors as well.) *So maybe it is a 20 pin
connector. In which case, a modern 20 or 24 pin supply could be
used to power it. We use color scheme on the wires, as a partial
way of correlating whether the thing is standard. (A multimeter is
used, to be absolutely sure.) In terms of necessary ratings, you
start with what is *printed on the old supply, to understand what
might be good as a replacement.

This project is do-able, but it will take time and consulting
as you go. It would help if you have another computer to use,
while you're coming up with a solution.

If I had more pictures to go by, it might be possible to say
more about the thing. But what little I can find, is not
enough to offer any definite guarantees about anything.

Open the computer, and compare what you see, to Wikipedia
articles. See the "variants" section in the first link, which
has dimensions for some of the motherboard types.

http://en.wikipedia.org/wiki/Atx

http://en.wikipedia.org/wiki/FlexATX

http://en.wikipedia.org/wiki/NLX

http://www.pcguide.com/ref/mbsys/mobo/form_NLX.htm

Now, after seeing this answer, you'd understand why I'd tell you
to *only* purchase regular ATX form factor used computers in the future :-)
The small stuff is nothing but pain, when it breaks. There are
small power supplies around, but not at your local computer store.
They'll look at you with this puzzled look on their face, if you
ask. You'd have better luck at a computer recycler.

* * P


Thanks for that, I'm amazed at the effort. I will bear it in mind in
a minute as I'm headed to where I might be able to salvage things, but
also to see what I can afford new or custom built without an o.s., as
it does sound like a bit of a highly compromised mess to do the
transplant with this odd size.

And I can't see a motherboard model name/number anywhere but I imagine
that relevant detail was on the spec page you showed me.

Anyway, fingers crossed....