[Beowulf] Cluster newbie, power recommendations

[Jim Lux]

At 03:58 AM 3/21/2006, Robert G. Brown wrote:
>O
>Yeah, that looks like it.  Kinda cute in its own way.  And you don't
>"have" to buy stock aluminum or steel and cut and bend it into shelf
>trays for the motherboards, BTW -- there was a design somewhere that
>mounted the motherboards onto cookie sheets and "racked" them in a
>standard cookie-sheet rack, or a rack like the ones they use in
>cafeterias.  Slide in, slide out.

For those of you rushing out for the latter approach (which is very clever, 
and inexpensive)..(and, since I was just out buying sheet pans: to bake on)

Standard commercial "half sheet" pans are 18"x13" nominal and cost <$10. 
They're also called Jelly Roll pans, and have a 3/4" to 1" rolled lip, 
which makes them quite stiff.  There's also a "full sheet" 26x18x1 (and a 
slightly different one called a full sheet cake pan that's 24x16x2 or 
24x16x3). And, of course, a quarter sheet (but I've only seen them in 
catalogs): 13x9x1.  Some of these made for home use are slightly smaller (I 
don't know why.. maybe to fit in more ovens?) and have exotic coatings and 
materials (of course, I MUST HAVE that $100 plasma sprayed aluminization 
over a steel pan with a special anodized coating to use with my $50 
silicone slip sheets.. instead of the sheet of parchment paper on a $10 
aluminum pan)

These things are all available from all sorts of sources (including, I was 
amazed to find, Amazon.com).

But, what you really need is the slick rack with the rails to hold the pans 
spaced just the right distance apart.  Well, for instance, from Gill Mfg:
http://www.gillmfg.com/item.php?product_id=1

or, the "Rack and Roll":
http://www.gillmfg.com/item.php?product_id=12

or, for those of you needing a smaller, more portable version:
http://www.restaurantequipment.com/CAMCARRIERS.html

This looks like it's available in 2 1/8" spacing and 1 1/2" spacing.

But those all look like the might not have enough ventilation, so you may 
want something more like:
http://www.food-equipment.com/sheet_pan_cart.htm

The latter place has the sheet pans for $6.25 (half sheet) and $7.25 (full 
sheet)

Anyway, lots of this sort of thing available...I imagine they do turn up 
used (when restaurants go bankrupt, for instance), but they're not all that 
expensive (a few hundred bucks) and a used one might be pretty beaten 
up.  They DO have nice casters though.


James Lux, P.E.
Spacecraft Radio Frequency Subsystems Group
Flight Communications Systems Section
Jet Propulsion Laboratory, Mail Stop 161-213
4800 Oak Grove Drive
Pasadena CA 91109
tel: (818)354-2075
fax: (818)393-6875