IIRC,

Any upgrade which does not replace the "box", meaning that the serial number
sticker on the outside of the SPU chassis does not change, ABSOLUTELY MUST
NOT change the HPSUSAN number.

Any upgrade which changes the system model number (generally adding CPUs
will do this) ABSOLUTELY MUST change the HPCPUNAME value.

If you find that *your* upgrade resulted in different results than above,
complain to your CE.

G.