It appears that there are two version of the nwsp2 on the market.
The classic version as we knew it and that has 256 MB of RAM and a 6281 SOC (ARM kirkwood processor) and recently a "Lite" version appeared that has only 128 MB of RAM and a 6192 SOC (ARM kirkwood processor). Both processors run on 800 Mhz
On the Lacie pacakge there is no indication which version is inside.
The kernel currently in use in the fvdw-sl firmware only supports the nwsp2 classic version. Thats the reason why on some nwsp2 the firmware did not run, those nwsp2's appeared to be "lite" versions.
In the meantime a new kernel is compiled for our firmware based on linux 2.6.39.4 This kernel will support as well the nwsp2 classic and the Lite version. It will be released with fvdw-sl-11-0
Below a picture form the bottom side of the nwsp classic and Lite version, this could help you to identify if you have a classic or lite version.
PS On the Lacie package there is no indication which version is inside, so when you buy you have to take it out of the package to see which version it is
More pics of the PCB's (needs disassembling of HDD)
nwsp2-classic-top view
nwsp2-lite-top-view
nwsp2-classic-bottom-view
nwsp2-lite-bottom