I've a DB server ASE 12.5.1 running. And now I'll have to restore all the data in a new server.

Is it possible to restore a DB dump in a different server with different hardware?

How can I accomplish to do this?

If a different platform, you'll have to create the tables and bcp the data across.

From ASE 12.5.2 You can dump and load a databases across platforms with the same endian architecture.
From ASE 12.5.3 You can dump and load a databases across platforms with different endian architecture.