Tandy 1000 SX

The Tandy 1000 SX was the lower-end sibling of the TX, and was essentially an upgraded reissue of the original Tandy 1000. It used a 7.16 MHz 8088-2 processor, had 384k of memory (upgradeable to 640K on the motherboard,) came with either one or two 5.25" internal floppy disk drives, had the light pen port (not a serial port) like the original Tandy 1000, and lacked the volume control and headphone jack of the TX (also like the original 1000).