the introduction of the LC, the lowest resolution supported on color Macs had been 640×480. Many programs written for color Macintosh II family computers had assumed this as a minimum, and some were unusable at the lower resolution. For several years software developers had to add support for this smaller screen resolution in order to guarantee that their software would run on LCs (as well as Color Classics which use the same resolution). Overall, general performance of the machine was disappointing due to the crippling data bus bottleneck, making it run far slower than the 16 MHz 68020-based Macintosh II from 1987, which had an identical processor but ran almost twice as fast. One difference between the Mac II and the Mac LC is the latter had no socket for a 68851 MMU. Therefore, it could not take advantage of System 7's virtual memory features. The standard configuration included a floppy drive and a 40 MB or 80 MB hard drive, but a version was available for the education market which had an Apple II card in the PDS slot, two floppy drives, and no hard drive. The LC was the final Macintosh model to allow for dual internal floppy drives. The LC, as with other Macs of the day, featured built-in networking on the serial port using LocalTalk. Ethernet was also available as an option via the single PDS slot. If the single expansion slot was a limitation, multifunction cards were available combining Ethernet functionality with an MMU or FPU socket. Apple IIe Card The Apple IIe Card for the PDS slot was offered in a bundle with education models of the LCs. The card allowed the LC to emulate an Apple IIe. The combination of a low-cost color Macintosh with Apple IIe compatibility was intended to encourage the education market to transition from aging Apple II models to the Macintosh platform instead of to the new low-cost IBM PC compatibles. Despite the LC's minimal video specs with a 12" monitor, any LC that supports the card can be switched into 560×384 resolution for better compatibility with the IIe's 280×192 High-Resolution graphics (essentially doubled). Models Introduced October 15, 1990: Macintosh LC: 2 MB RAM, 40 MB HDD. Timeline References External links Apple Macintosh LC (Original) Specs at everymac.com. Mac LC at lowendmac.com. LC I LC I Computer-related introductions in 1990