No, SQL Server does not support that. You can use a federated databases but this is very complex to do, and to be frank odds are your database and application aren’t big enough to need to do this.
If you have a 32bit SQL server you should be upgrading to a 64bit server, adding more RAM, and more CPUs to the server.
Can you describe your systems in more detail? What kind of servers do you have? What sort of workload do you have? How many transactions per second do you support?
Have you already fixed any indexing problems that exist?