Server Juggling

Hi. I’m setting up a Joomla based site for a domain that hosted elsewhere. I have the domain and user setup in the control panel, mysql db and the files have been uploaded to the IP address listed in DNS settings. How do I access the files via a browser to install and configure? I would have assumed it was http://Dreamhost DNS IP/~username ? until I change the NS servers to Dreamhosts?

thanks in advance for any help