I just tried a little test in response to some questions about how the unit might perform with more RAM. I had a 1 GB SODIMM of PC2700 (DDR-333) on hand so I tried that in place of the stock 256 MB of DDR-266.
It doesn’t boot at all. It seems that the BIOS can’t handle more than 512 MB of RAM. I’ll get a 512 MB stick and try that tomorrow.