It would be nice if the SAM Hardware Health could also pick up the Asset Tag field along with the Serial Number and Product Number that it already returns as shown below.
Are you referring to the Express Service Code?
I think the Express Service Code is for the Dell range of products as its not something I'm familiar with on HP tin.
On HP kit you can set Server Name, Asset Tag and some other fields in the BIOS. Typically this will match the physical asset tag attached to the server chassis by the purchasing company. I noticed in VMWare ESXi5 U1 it now can pick up this field so was hoping NPM/SAM could do the same. I've done a MIB walk but it doesnt seem to be getting the value from SNMP, so not sure how/where it gets it from.