Gecko's CPU Library

Rise mP6 processors

Introduction: October 1998

On the 13 October 1998, Rise Technology Company unveiled the mP6 family of microprocessors at the Microprocessor Forum. Rise Technology Company was an until then unknown fabless x86 CPU designer which was founded in 1993. Although the Rise Technology Company headquarters is located in Santa Clara California, they were finacially supported by some 15 investors from Taiwan. Among those investors are companies like Acer and Umax.

The x86 microprocessor market has always been tough to enter and hard to succeed in. But at the time only Intel and AMD supplied the market. Cyrix was virtually out of the business and IDT in serious financial trouble and looking openly for partners. So the third supplier space was vacant and with a little luck Rise could succeed in the x86 business.

The mP6 is a 5th generation CPU, it has a superscaler design which is tailored to multimedia applications and low power consumption. It was targeted at the notebook and sub $1000 PC market. Low power consumption and well balanced price/performance ratio were main topics at the introduction.

Technical strong points of the mP6 are the ability to handle three MMX instructions per clock cycle and a super pipelined FPU unit. With the introduction Rise emphasist the low power consumption of the mP6, the power management is built into the core. When parts of the CPU are not needed these are automatically shut down to save energy. Typical powerconsumption for the 200MHz (PR266) version is little over 6 Watts. Designed for the Super7 it is able to utilize a 100MHz Front Side Bus. In order to save on manufacturing costs the die size is only 107 mm2 and manufactured at 0.25 micron. The mP6 was only manufactured in BGA packaging and Turbo Thermal BGA (T2BGA), for use in a socket the BGA package was installed on a small PCB with a Socket 7 pinout (BPGA). Core voltage is 2.8v and 3.3v for the I/O.

Rise always stressed that the mP6 had a "well balanced price/performance ratio", but what was the realworld performance? When compared to the AMD K6-2 and the IDT WinChip 2 the Rise mP6 performed slowest of the three at the same PR speed. While it should have been at least as fast or faster than the other CPU's looking at the specifications. What then slowed the mP6 down? The cause of the low performance can be found in the small size of the L1 cache of only 16KB. The K6-2 and the WinChip 2 both have 64KB to feed data to the core.

After just over one year actively participating in the x86 Desktop market Rise left it to Intel, AMD and newcommer VIA (who bought IDT and Cyrix) and concentrated on the market for information appliances. SIS and SGS Thompson bought a license for the mP6 core design so maybe we will yet see a comeback of the shortlived mP6!