to the very different hardware architecture of the Risc PC, including an ARM 6 processor, 16- and 24-bit colour and a different IO chip (IOMD), RISC OS 3.50 was not made available for the older Archimedes and A Series ARM2 and 3 machines. RISC OS 3.5 was somewhat shoehorned into the 2 MB footprint, and moved the ROM applications of RISC OS 3.1 onto the hard drive; this proved so unpopular that they were later moved back into ROM. This version introduced issues of backward compatibility, particularly with games. RISC OS 3.60 followed in 1995. The OS features much improved hard disk access and its networking was enhanced to include TCP/IP as standard in addition to Acorn's existing proprietary Econet system. The hardware support was also improved; Risc PCs could now use ARM7 processors. Acorn's A7000 machine with its ARM7500 processor was also supported. RISC OS 3.6 was twice the size of RISC OS 3.5, shipping on 4 MB in two ROM chips; components that had been moved onto disk in 3.5 (the standard application suite and networking) were now moved back into ROM. RISC OS 3.70 was released in 1996. The primary changes in the OS was support for the StrongARM processor that was made available as an upgrade for the Risc PC. This required extensive code changes due to StrongARM's split data and instruction cache (Harvard architecture) and 32-bit interrupt modes. RISC OS 3.71 is a small update released to support the hardware in the Acorn A7000+ with its ARM7500FE processor. The FE offered hardware support for floating point mathematics, which until then was usually emulated in one of the RISC OS Software modules). RISC OS 3.60 also formed the foundation of NCOS, as shipped in the Acorn NetChannel NCs. Demise of Acorn Computers Ltd Acorn officially halted work in all areas except set-top boxes in January 1999 and the company was renamed Element 14 (the 14th element of the periodic table being silicon) with a new goal to become purely a Silicon design business (like the previous very successful spin off of ARM from Acorn in 1990). RISC OS development was halted during the development of OS 4.0 for the RiscPC 2 ("Phoebe 2100"), whose completion was also cancelled. A beta version, OS 3.8 ("Ursula") for the original RiscPC, had previously been released to developers. The project code names of Phoebe (for the hardware), Ursula (for the