Date : Mon, 06 Mar 2006 11:17:55 +0000
From : Fragula <fragula@...>
Subject: *** SPAM *** Re: Warning: Sad case on list!
Hi Jules!
Jules Richardson wrote:
> Complete with minaturised freon cooling system? :-)
You could get away with pure water on an FPGA. And the Cray-2 had a much
more visually impressive cooling system.
<blush> I did a PC about 5-6 years back, I hasten to insert that this
was for a mate who was going through a bad time and needed cheering,
that had a waterblock & peltier on the CPU (was a K6-II at about 500MHz.).
The cool bit was the "twin towers", a pair of 6' tall 8" diameter
plexiglass tubes set in a black fake slate base that had uplighters in
it, and joined by a transparent "syphon balancer" tube at the top. The
"Twin Towers" was bought in some novelty shop (might have been the
Gadget Shop) and didn't cost the earth. ISTR it was about £45.
The water was pumped into the bottom of one tower, and out from the
other. But that's still not the cool bit. Two fairly high pressure, but
low flow, air pumps (Aquarium shop, but they had to be a very specific
make and model in order to be able to produce enough pressure without
popping their diaphragms) blew air in through a "bubble tube" (a kind of
porous material that only allows /tiny/ little bubbles through) which
was spiralled in the bottom of each plexi tube. The result was very
pretty indeed (as a living room ornament) and did a sterling job of
cooling the CPU, allowing an FSB overclock from 66 to 100MHz IIRC. Which
is 50%. The Peltier element (ordered in from St. Petersberg, Russia, the
only place we could get a big enough one!) consumed a rather alarming
10A@... (seperate supply) but managed to keep the CPU down to the point
that we had to insulate it to stop condensation from freezing on the CPU
edges.
There were problems to come though. Evaporation (aggravated by the
warmed water and the bubbles) meant that the syphon coupler sometimes
took air and stopped working. The right hand (in from computer) tube
would then overflow. At one point the bloke dropped the PC down to floor
level (it was on a shelf above monitor height normally) and the pressure
blew a pipe off a connector on the water block. Finally the peltier
element failed, a dead peltier making a great insulator, bizarrely the
CPU survived, but the motherboard drew so much power when the CPU
overheated that it melted the ATX power connector, and burned a load of
tracks off the board.
But it is doable.. (ahh.. now what about my 80186 2p? >;)
No seriously, That's what I was doing during Live Aid, back in 1985. It
was a hot day, and my unheatsinked 8271 (on a DFDC) was overheating and
throwing errors. So I needed to cool it quick. Naturally I stuck my
finger in my coffee, and put a few drops on the FDC, which promptly
dried leaving a crusty residue. For many months after that, there was a
bottom half of a tobacco tin stuck to the top of both 8271 and 1770,
which frequently got topped up with water, or when desperate, coffee,
Red Stripe, or Newcastle Brown. - I'm seriously not kidding here. It did
the trick, evaporation cooling. I've since tried heatsinks and fans, but
when the Model B is fully populated (err. i tend to ram too much in kit
in the case, i know..) nothing seems enough. So I'm probably going to
settly for One 40mm fan pulling from the PSU into the motherboard area,
and some sort of waterblock on the 8271+1770, One on the video ULA, and
one that other chip that gets real hot. ISTR it might be the system VIA,
but I'll try swapping that one out first.
Not sure what to do about a radiator.. I have a nice 12" square one with
10" mains fan, from a scrapped PCB Waterdrill. That could go on top of,
or behind a cub quite nicely. It /does/ mean plumbing through the back
of the beeb though <sigh> And if I get a GoMMC, I'm going to have to put
it up on the Integra-B board, which means a "power bulge" in the top of
the BBC anyway. (I have a spare tatty lid for modding.) Gahh.. I was
hoping to keep it all internal, maybe even to be able to put the lid on
One Day.
> We're hopefully picking up our first Cray over the next few weeks (sadly
> I think it's an EL98 though, not the iconic horseshoe monster! :-)
Nothing too sad about an EL98. Oh sure its not a /real/ Cray (I'm
gradually aquiring a fixed opinion about this, and it flies in the face
of everything you might think, but has an underlying philosophy i'm
sure) but is an aircooled CMOS implementation of the original YMP-1
IIRC. Another company made it to offer a "dirt cheap" competition.
So Cray Research bought them out and marketed the machines themselves.
The '98 is an evolution of what they bought in.
The smaller "deskside" EL-92/94 Crays are not so much fun, slow and very
noisy, but I'd probably make space for one here given the chance.
'Aint seen any on Ebay with system hard disks (standard SCSI stuff for
the main array, ESDI for the IOP, which is probably more critical!)
intact though, and the prices of Unicos/Cray C installs are utterly
prohibitive (like 100K each!) and that's IF Cray decide to (a) support
it (b) like you, etc..
TBH a non-functional machine would just be an oversised paperweight to
me. There were a set of 3 CMOS Y-series, one of which was a '98 for sale
a while back. No hard disks or RAM, but the cabs, racks, supplies,
processors etc. appeared to be intact. Nice museum items after a tarting
over. However the guy couldn't make a $300 reserve for the set! I
thought about it (might have a few secret weapons to use for hardware
aquisition, but not software) but decided the £1000 shipping charge made
it non-viable. If I'd had systems available I'd probably have them right
now. <Sigh> Actually the 98 isn't such a bad machine@...
The ACW has only hung in there due to its functionality as a BBC. I dare
not use PANOS as it doesn't appear to have a complete system, and I
don't have a workable distribution kit to reinstall at the mo.
>
> Wroughton have a Cray 1a and a Cray 2 though, so we have our eye on one
> of those...
>
Hmm.. Nice.. Pretty machines both. Those /are/ museum pieces, even as
ornaments. Beware the coolant though!
> Of course what I *really* want is some Connection Machines hardware for
> sheer coolness factor!
Cool, yes, pretty, yes. But Dirty! Dirty! Dirty!
> Am I off topic yet? ;)
Uhh.. We are talking about 2nd processors, processor architectures with
a view to, FPGAs, cooling systems, and BBC micros, right? Oh.. Well I
was.. Honest :-)
Seems a holy war might kick off soon, I've been here 3 days now, so its
due i'm sure. At least nobody has mentioned the Mohammed Cartoons yet.
<gd&r>
Cheers!
M.