1.)First of all you need to remove the computer name from your PDC. This causes conflict as it will have a diff ID.
2.) Log on as an admin (locally) on the wrkstation and change the domain to the domain of your PDC. To do this..right click network neighbourhood..properties..then click change on the ID Tab..
Where its says "Members Of" choose the Domain and make sure the domain you type is the same as in your PDC. You can put a tick on "Create account.." then below that use your domain admin as the user.
3.) Things you should make sure:
i. your cable and network card are OK
ii. the domain name you type is the same as the PDC domain.
hope this helps