Cpu I/O Signal Considerations; Figure 121. Ich4-M Cpu I/O Signals With Processor And Fwh - Intel 855GM Design Manual

I/O Subsystem
11.11.

CPU I/O Signal Considerations

The Intel 82801DBM ICH4-Mhas been designed to be voltage compatible with the CMOS signals of the
Intel Pentium M / Intel Celeron M processor. For Intel Pentium M / Intel Celeron M processor -based
systems, the ICH4-M's V_CPU_IO rail uses the same 1.05-V voltage as the V
the GMCH. It is important to verify that the voltage requirements of all CPU and ICH4-M signals are
compatible with the FWH as well. See Section 11.7 for FWH details. Figure 121 shows a typical
interface between the ICH4-M, CPU, and FWH. See Section 4.1.3.5 for recommended topologies and
routing guidelines.

Figure 121. ICH4-M CPU I/O Signals with Processor and FWH

238
FERR#
Processor
Output Signals
INI
T#
FWH
Intel
CCP
V_CPU_IO @ 1.05 V
ICH4-M
9
®
855GM/855GME Chipset Platform Design Guide
R
rails for the processor