Retrieving seismic data by a data server. At least some of the illustrative embodiments are methods including: retrieving a seismic data slice from a seismic data volume, the datums logically organized in parallel layers, the retrieving by: sending a request for the seismic data slice from a client computer to a data sever over a network connection, the request spans at least a quarter of the layers in the seismic data volume, and the data server is remote from the client computer; extracting data values associated with the seismic data slice from the seismic data volume by the data server; sending, by the data server, datums residing within the seismic data slice, the sending such that at least some cache lines of a processor of the client computer filled responsive to the request comprise datums that span more than one layer; and then rendering the seismic data slice on a display device.