In hot water (really hot air, but that's something else)

[Net Llama!]

I don't think this is an overheating problem.  Especially since the CPUs 
should speed back up once they cooled down.

How much wattage is the power supply?  What other hardware do you have 
in this box?  Are all the components brand new?  Have you looked at your 
messages log for errors?

Kevin O'Gorman wrote:
> I may have done something foolish.  Nothing new.  But I cannot tell
> for sure, and I could use advice.
> 
> I bought parts to make a dual-Xeon machine, with DDR memory.  It was
> to be my main server at home.  It's up and running, partly, and it's
> about as fast as I had hoped.  But after a while, it suddenly becomes
> S U P E R    S L O W.  Think PC/XT speeds.
> 
> I understand that Xeon CPUs have heat sensors, and that when they
> detect overtemperature, they slow down.  That's good as far as it
> goes, but I don't see why they would be overheating.
> 
> The chassis is a tall tower (with a sort of upper part and lower
> part).  The upper part has the disk drives and power supply, and
> is separated from the lower part by a piece of sheet metal with
> a hole big enough for all the cables I'll need.  The lower part
> has the motherboard with CPU's, my one add-in card (SCSI controller:
> adaptec 39160) and a mess of fans.  
> 
> The power supply has an exhaust fan, and there's quite a big
> auxiliary exhaust fan just above it.
> 
> In the lower bay, there's a similar big exhaust fan, both CPUs
> have wind-tunnel head sinks with fans pointing towards the back,
> and I've put and additional two fans pulling air in the front
> and aimed at the CPUs.  When I touch the heat sinks, there's no
> noticeable warmth at all, even right down by the CPU chip.
> 
> This whole afair is sitting on my table, next to my monitor.
> The first two times it went into molasses-mode, all the skins were
> on it.  I've got one side exposed now, and nothing bad has happened
> so far, but sometimes it has taken 18 hours of running or so for
> mollasses to begin.  This morning it only took about 1/2 hour.
> 
> The room is not particularly warm, though it's not air-conditioned.
> I wouldn't run the A/C right now if I had it.
> 
> Any ideas?  Is there something besides heat that could make these
> babies slow down?  Is there something I could test?  Can I make
> them speed up without a reboot?  Is that a good idea?
> 
> Was it foolish of me to gear up for Xeons?

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
L. Friedman                       	       netllama at linux-sxs.org
Linux Step-by-step & TyGeMo: 		    http://netllama.ipfox.com

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