FYI, this machine has been working fine now for a few weeks. Apparently the RAM from Crucial was at fault, as I sent the RAM back for replacement and received two brand-spankin' new DIMMS back from them. Reinstalled, now running at 3 GB of RAM and all appears to be purring along quite nicely.
Thanks to all who contributed to this thread! And Silverkeeper seems to be doing its thing just fine after I reset it with a new set of backup instructions.
Chris K
