Application Note
(Includes Differences for 970FX to 970MP)
IBM PowerPC® 970MP RISC Microprocessor Preliminary
7. Timings
Page 20 of 25
AppNote_970FX-MP_Differences_Body.fm.1.0
November 15, 2006
6. System Design Information
The 970MP supports a 24:1 bus ratio for test purposes instead of the 16:1 bus ratio supported in the 970FX.
The BUS_CFG(0:2) pin setting for this 24:1 bus ratio is ‘110’, which is the same setting that was used to
select the 16:1 bus ratio in the 970FX.
Unlike the 970FX, ANALOG_GND is not shorted to GND within the 970MP. Please refer to the IBM PowerPC
970MP RISC Microprocessor Datasheet for the proper filtering recommendation.
7. Timings
Note: Timings are very processor and technology specific. It should not be assumed that timings remain
equivalent between any of the PowerPC microprocessors designs. Timings for each of the IBM PowerPC
microprocessor family of products are located within their specific electrical specification, referred to as the
“Datasheet.” Contact your IBM Sales or technical support group for the PowerPC 970MP RISC Microproces-
sor Datasheet.
8. Package

8.1 Design Considerations for a 970MP Thermal Solution

The 970MP package differs from the 970FX with respect to:
• Die size/dimension
• Position of the capacitors on the die
8.1.1 Die Size
A thermal solution for the 970MP needs to consider the die size (refer to Table8-1 and Figure 8-1). Due to a
higher power density, heat pipes may be stressed and pushed quite close to their boiling point. If the liquid in
the pipe boils, the cooling system will fail. The PowerPC 970MP is on the cusp of air versus water for a
cooling solution.
Table8-1. PowerPC 970FX, and 970MP Die Size and Dimensions
970FX 970MP
Die size 66.2 sq mm 153.8 sq mm
Die Dimension 7.07mm x 9.36mm 13.23mm x 11.63mm