On Thu, Mar 29, 2007 at 06:14:24PM -0700, Michael Hannon wrote:
> Greetings.  One of the profs here has got a Dell Optiplex 620 running SL
> 4.4.  It has an Intel Pentium D chip that is dual-core-capable, and it
> has the capability enabled.
> 
> >From time to time the owner has had problems with the system hanging.
> He usually solves the problem with some stupid computer trick, such as
> cycling the power, etc.  But yesterday he had one of the usual hangs,
> except that it was one from which he could not recover.
> 
> The problem is very similar to one that was reported on the SL-users
> list not too long ago.  In more detail, the system either has a kernel
> panic during the boot sequence, or it boots all the way and allows a
> login, but almost immediately has a "hard freeze" that requires a power
> cycle to thaw.
> 
> We've run the Dell diagnostic utilities to test processor, memory, and
> video, but we didn't find any problems.
> 
> The system is running the latest kernel,  but it will not boot reliably
> with any of the four SMP kernels currently installed on it.
> 
> We've tried all of the voodoo that I saw mentioned in the previous
> discussion (run-level 3, no "rhgb quiet" on the command line), but the
> only thing that seems to work reliably is to boot with the uni-processor
> kernel.
> 
> This is probably an acceptable work-around for the time being, and my
> hope is that when we do a fresh install with SL 5, we'll all be happy
> again.  But I wonder if any of y'all can provide any further insight
> into this.

Could the machine be overheating, by any chance?  I've had similar
difficulties with a couple of Dell Optiplex 620 Small Form Factor
machines running SL305.  They would get into a state where they would
only boot with the uniprocessor kernel, but if you left them off
overnight to cool down, they would boot the SMP kernel again.  Several
other identical machines kept on working fine, though.
Eva.