Machine is a Compaq dx5150 64 bit desktop with 3Gb of memory.  It has bee
n
having no problems with 64 bit SL5.3.  Before upgrading to SL5.4, I thoug
ht
I'd be cautious and try out the live dvd, but it won't boot.  Even if I t
ry
"failsafe", the boot sequence prints the "ok" after starting udev and the
n
the screen goes blank and never comes back again.

I have no other reason to suspect the machine itself.  The only time I ne
ed
to reboot is for new kernels or drivers.  I tried the memtest program on 
the
dvd and it didn't report any problems.

Md5sum gives the right answer for the dvd containing the iso image.  I
downloaded and burned it again just in case, but it didn't make any diffe
rence.

The dvd drive is ok as far as I can tell.  I'm able to boot and run from 
an
old Knoppix dvd.

Any suggestions for what to try?

Thanks