I have a Win 2003 x64 server with SQL Server 2008 R2 Standard that is only used for reporting and all reports even the really small ones load slow. The only change I have made is demoting the old Win 2003 PDC and BDC after I brought 2 Windows 2012 R2 Domain Controllers online. I have checked all the network adapters and they have the correct IP, subnet, gateways, and DNS. I have Flushed DNS too. I don't see any errors in the logs so the only thing I can think of is there is some SQL setting deep in the database that references the old Domain Controllers.
BTW... I have just finished updating the entire network with CAT 6a, but that was after the slow behavior began. I have Cisco Catalyst Gigabit Switches that are stacked so bandwidth is not an issue here. The server even has 4 10GB NICs that are teamed. The host server is a huge 8 core...
