custom hardware (was: Xbox clusters?)

[Velocet]

On Wed, Nov 28, 2001 at 05:11:09PM -0500, David Vos's all...
> On Wed, 28 Nov 2001, John Burton wrote:
> > Ummmm....speak for yourself. I've been putting together these "self
> > assembled beige box" for many years and currently have about 5%
> > component DOA rate, and about another 1% infant mortality rate (crap

> There is one computer in our cluster that would make me think twice before
> doing a custom build.  I prefer to call it the node from heck.  It only
> has one problem: it won't boot.  If you press the power button, the
> powerlight flashes while the cpu and case fans turn a quarter turn, then
> nothing.  You have to wait a minute before you even get that reaction
> again.  (Sounds like a short somewhere).  The problem only surfaces if the
> computer has been off for a little while, and nearly every time at that.

> Since there is not a single piece of hardware that was present in each
> case, I feel forced to conclude that there must be something (power cord?)  
> that is braking the power supplies.  I have not seen this problem on any
> other computers.  This is the point at which I would love to put the whole
> computer back in a box and send it to the reseller.

I saw this EXTREMELY SIMILAR type of situation when I went and fried
3 power supplies in a row trying to boot dual athlons on the Tiger XMP
board. :) They ran fine for 1-5 minutes then the power supply blew. Then
the power supply would never fully turn on again, just a quarter turn
of the fan kinda thing. Those were 300W supplies, and you need 350W's
(30A min on +5V, the 300s were 25A, the 350s do 32A) to run the dual board.

Now things are fine (enermax 350W supplies are nice).

So it might be that... What kinda cpu, how many drives, how much ram
and how big are your supplies?

Anyway, this kind of event DOESNT exlcuse the XBOX from having these
problems too, except you dont get to return it and you dont get to
take it apart to see which particular component piece in which combination
displays the problem.

/kc
-- 
Ken Chase, math at velocet.ca  *  Velocet Communications Inc.  *  Toronto, CANADA