I want to load part of DBPedia 2014 (17 GB uncompressed) in Virtuoso 7.2 with 3 GB RAM and 2 cores CPU. However this suggest at least 32 GB RAM and 4 cores CPU to load in 1.5 hours, but my attempt to load it in a 32-bit Operating system didn't finish even in 13 hours. Does it drastically get longer?
The instructions you linked were written about Virtuoso 7.0 and DBpedia 3.9. It's worth noting he's put out an update based on Virtuoso 7.1 and DBpedia 2014 (a/k/a 3.10) -- but that's still far behind the times.
Virtuoso is now at 7.2.1, which brings many, many improvements vs the older versions. I can't say that I'd recommend doing this load on the very underpowered machine you describe, but it should eventually succeed.
You might also consider using the recently published pay-as-you-go DBpedia AMI on Amazon EC2, which eliminates the need for any loading by you.