Probably your query is too general. There are so many aspects of Software and Hardware (design, requirements, development, languages, models, metamodels, functions, operating environments, architectures,...) that it would be very hard to find an ontology covering all those topics. 

Only Cyc claims to build ontology of everything, http://www.cyc.com/platform/opencyc/downloads. Surely, you can find inside many concepts related to software and hardware. 

Hi Piotr, thanks a lot for your response.

Actually, I am looking for light-weight models that represent (hierarchies of) software items (like e.g. OS, source code, compiler, word processor etc.) and hardware components (e.g. motherboard, graphics card, memory etc.).

At this point, I would like to stay away from these vast generic ontologies like Cyc.

Any help is welcome, Thanks a lot in advance!

You should take a look at this page: www.ebi.ac.uk/efo/swo

Also a couple of ontology look up sites:

EBI: http://www.ebi.ac.uk/ontology-lookup/

Bioportal: http://bioportal.bioontology.org/ontologies

http://www.obofoundry.org/

also you could post a question here: [email protected]

You might want to take a look at the FIPA device ontology specification: http://www.fipa.org/specs/fipa00091/PC00091A.html#_Toc511707121

Thanks a lot Suparna! Actually, this is quite close to what I wanted. Btw, I couldn't find an OWL/RDF implementation at the FIPA site, but found a small CoBrA extension here (http://cobra.umbc.edu/ontologies-2003-11.html). Any additional resources are welcome, though!