The Tandy 1000 SL and SL/2 feature an Intel 8086 processor running at 8 MHz. This is socketed, and thus upgradeable with an NEC V30. The SL came with of RAM preinstalled, whereas the SL/2 offered . Both machines could be expanded to , although the graphics controller reserved a portion of this memory, yielding only available the operating system, even on systems using add-in ISA graphic cards. The SL line had the mic/earphone ports, volume knob and reset button on a small satellite board. A jumper on the board allowed the user to change the microphone input to a line-level output. The SL series offered five 8-bit XT-compatible ISA slots, and did not come with pre-installed real-time clock chips, making them optional upgrades in the form of the plug-in Dallas DS1216E SmartWatch.