Previously IBM servers based on AMD Opteron CPUs did not share the xSeries brand; instead they fell directly under the eServer umbrella.

[citation needed] 1998–2001 server line; Not to be confused with a software IBM product with a similar name, NetFinity (notice the capital F).

The numbering scheme started off similar to that of the IBM PC Servers, but additional ranges were added, like the entry-level 1000 model later on.

From a numbering perspective the AMD servers did fit into the xSeries range, under the similar x335 and x336 Intel processor products.

These systems are effectively the same as the previous IBM branded models, but with a Lenovo badge.

At the time of this writing, System x is being discontinued and replaced by the Lenovo ThinkSystem family of Intel servers.