Installing Drupal

I have installed connction manually. In my settings.php,

Additional uncaught exception thrown while handling exception.

Original

PDOException: SQLSTATE[HY000]: General error: 2006 MySQL server has gone away: DELETE FROM {semaphore} WHERE (name = :db_condition_placeholder_0) AND (value = :db_condition_placeholder_1) ; Array ( [:db_condition_placeholder_0] => menu_rebuild [:db_condition_placeholder_1] => 11056351385474d0c4089f15.97842661 ) in lock_release() (line 254 of C:\wamp\www\mica_distribution-7.x-9.2\includes\lock.inc).

Additional

I have a new project and the client want to buy a server to host the website. I already know some of the ram php need to run intallation but what king of hardware a drupal site need? How many Hard drive space? Raid? RAM? I know the hardware change base in trafic, but what about a minimal Requirement?

I have been playing with the installation of Drupal for two days now. Is there any one out there that would like to make some extra money?

issue should be removed by board admins!

I have a drupal 7 installation at mysite.com. I want clients to preview their sites at (ex: mysites.com/client1). I am using a Virtual Private Server.
I think I am confused about virtual hosts and mutisites and a VPS.
Here is what I though I could do:
Install drupal 7 at mysites.com.
Set up a default site using "settings.php" in the default folder. This is fine. If I navigate to mysite.com, I get the standard drupal installation.
I created a new folder called "client1" in mysite.com/sites
I created a new database called "client1database".