You can specify the PXE service points computer account to connect with the Configuration Manager 2007 database by selecting Use the PXE service point's computer account. If your network security model is designed to use a different account to communicate with the Configuration Manager 2007 database you can also specify a different account. To specify a different account, select Use another account and enter the network account that should be used or click Set button to open the Windows User Account dialog box. Specify the network account and network password that should be used for the connection. You must manually add the specified account to the SMS PXE Service Point Role (msdbrole_PSP) on the site database. For more information, see About the PXE Service Point Database Connection Account
Specify whether the PXE service point will create a self-signed certificate or if the certificate will be imported by the user. If you are in an environment that requires the PXE service point to create a self-signed certificate, you must set the expiration date in the space provided. In native mode environments the self-signed certificate option is not available and you must import a certificate from a trusted root certification authority.
To import a certificate, select Import certificate and then locate the certificate by clicking Browse, and then enter the password associated with the certificate.