Lenovo ThinkCentre A61, 2.1 GHz, AMD Athlon X2, 4000+, 1 GB, 160 GB, Windows XP Professional Lenovo ThinkCentre A61. Processor frequency: 2.1 GHz, Processor family: AMD Athlon X2, Processor model: 4000+. Internal memory: 1 GB, Internal memory type: DDR2-SDRAM. Total storage capacity: 160 GB. Operating system installed: Windows XP Professional. Power supply: 220 W. Chassis type: Desktop. Product type: PC. Weight: 20.7 lbs (9.4 kg). Product color: Black