<Tr> <Td> E-block </Td> <Td> 15th 64 KB </Td> <Td> other use (PCjr cartridges, LIM EMS) </Td> </Tr> <Tr> <Td> F - block </Td> <Td> 16th 64 KB </Td> <Td> System ROM - BIOS and ROM - BASIC </Td> </Tr> <P> The 640 KB barrier is an architectural limitation of IBM and IBM PC compatible PCs . The Intel 8088 CPU, used in the original IBM PC, was able to address 1 MB (2 bytes), since the chip offered 20 address lines . </P> <P> The first memory segment (64 KB) of the conventional memory area is named lower memory or low memory area . </P>

What is the maximum amount of ram that the original pc processor could access