A small step of progress to report.
I bought the D945GCLF2 board (Atom 330, dual core, Intel® EM64T, Hyperthreading) because of the Gigabit LAN (and all the other usual reasons (low power, blah, blah)). Tried booting NL2 v2.06. Got same "Unable to handle 64-bit address space for PCI".
BUT ... if you go into BIOS, at the main screen, the first item that's highlighted, being "Hyperthreading", if you DISABLE it, NL will boot
There's still a problem, though. The Realtek RTL8102
E is not recognized. If it helps ... be aware that even my tests with Windoze Vista64 and WinXP-SP2 installs both did
NOT initially see this on-board LAN. I had to install drivers from the CD supplied with the mobo.
So ... since you can boot now ... you can use the single PCI slot for a LAN card. I haven't tried that yet, but will update this post as time allows me to experiment further.
Hopefully NL v2.07 will support version
E of the Realtek.

Georg
Update 1: Ubuntu 8.04.1 (Live CD) works like a charm with the onboard NIC, and with Hyperthreading on (=default). So then I looked at Intel site for Linux compatibility (
Linux on this board). An interesting footnote says for some distributions "
Need external driver. Download Linux* driver for RTL8111c here.*". So, even though this is Realtek RTL8102
E, looks like drivers for
C might work. And notice minimum supported Linux kernel is 2.6.16.