ThinkPad A series
The A series was developed as a direct successor of the discontinued 700 series, but after Lenovo's re-introduction in 2018, it was considered a small branch-off of the T and X series with AMD hardware.
The early IBM models were mobile workstations, designed to cool and contain powerful graphics controllers for its era. They were also notable for being 3-spindle machines (with one Ultrabay), although the A3x models took an extra step above that and had two Ultrabays instead.
Unfortunately, the focus for more mobile workstations had taken over, and so the A series was discontinued in favor of the lighter T series 'p' models.