Central Admin site won't let anyone log in.

I am trying to set up our production multi-server farm.  I have run the configuration wizard after creating the configuration database manually using powershell, and Central Administration site loads fine when opened directly from the application server which it is hosted on while logged in as the setup user account.  However, if i am on any other server or machine, it prompts for credentials and doesn't accept anything.  Also, if i am on the application server hosting the central administration site, and i try to sign in as the farm administrator account, it will not accept those credentials.  It won't even then accept the setup users credentials.  I have to close IE then re-open the central administration page in order to be able to administer anything.

Here is a little more information:

• I already ran through the same type of installation on a sandbox machine in a single server environment, and it was working fine.  The only major difference at this time is that i am using separate accounts for the setup user and the farm administrator.
• I have tried to push forward with my deployment, however, i get an error when trying to set up the search service.  After running a set-spenterpriseSearchService command i get an error: "The specified credentials are invalid"
• I am using Kerberos authentication just like i did on the sandbox, and i have set up the SPNs for the SQL service account, farm admin account, application pool account, and the setup user account just in case.

I am at a complete loss on this one, it seems like it is not able to validate any credentials, but i don't know how to verify that at all.  I did try to verify kerberos was working, but i didn't see any security logs regarding verification of any account at all, so i don't technically know if kerberos is working or not.

Please help.  Thanks.