The upgrade went fine for the most part; puck is now running Gentoo on the system image and is plugged into a nice SmartUPS with monitoring.

The memory was not upgraded. Although Dell's support system claims the server was shipped with registered memory, when I opened the case I found unregistered memory. This is unfortunate, because the memory upgrade I purchased is registered, and therefore cannot be installed next to the OEM memory.

I guess I'll take the 20% restocking fee to return it and purchase the non-registered. Stupid Dell.