I would check that the multi-threading is checked on the PC.  If it is, then to check if the system sees both processors.  Press Control-alt-delete or right click on the task bar, bring up the task manager.  Select Performance and it should have  a CPU Usage History section.  If it has 2 graphs there then the OS see's both processors.  if you do things you should see most activity in one, but should see some in both.