You can use either of the two. You need first to create a Data Source pointed to each of your servers.
1. Go to Control Panel > Administrative tools > data sources. then go to System DSN tab. Click Add then choose SQL server for example. Then just specify the IP address at the server address field.
just explore or experiment from the field boxes....
2. Make use of the created Data source in qlikview using either ODBC or OLE DB connection.