Specifications
Intel
®
810E2 Chipset Platform
R
36 Design Guide
2.2.8.1. Power-Up/Reset Strap Options
Table 10 lists power-up options that are loaded into the 82810E GMCH during cold reset.
Table 10. Power Up Options
Signal Description
LMD[31] XOR Chain Test Select: LMD[31] is set to 0 for normal operation. It must be set to 1 to enter
XOR tree mode during reset. This signal must remain 1 during the entire XOR tree test.
LMD[30] ALL Z select: If LMD[30] is set to 1, it tri-states all signals during reset. For normal operation,
LMD[30] should be set to 0
LMD[29] Host Frequency Select: If LMD[13] is 0 and LMD[29] is set to 0 during reset, the host bus
frequency is 66 MHz. If LMD[13] is 0 and LMD[29] is set to 1, the host bus frequency is
100 MHz.
LMD[28] In-Order Queue Depth Status: The value on LMD[28] sampled at the rising edge of
CPURST# reflects if the IOQD is set to 1 or 4. If LMD[28] is set to 0, IOQD is 4. If LMD[28] is
set to 1, IOQD is 1.
LMD[13] Host Frequency Select: If LMD[13] is a 0, LMD[29] determines host bus frequency. If
LMD[13] is a 1, the host bus frequency is 133 MHz.
Table 11. Host Frequency Strappings
LMD[13] LMD[29] Host Bus Frequency
0 0 66 MHz
0 1 100 MHz
1 X 133 MHz
2.2.9. Voltage Regulation Differences
The Pentium III (FC-PGA w/256K L2 cache) processor requires the VRM or on-board voltage regulator
to be compliant with Intel VRM 8.4 DC-DC Converter Design Guidelines revision 1.5 or greater.
Important points to note regarding VRM 8.4 as follow:
• Celeron processor (PPGA) operates at VCC
CORE
of 2.0V, Pentium III (FP-PGA w/128-K L2 cache)
operates at 1.5V, and Pentium III 256K operates at 1.6V.
• Requirement for VRM 8.4 to support the Pentium III processor at speeds greater than 650 MHz has
changed from previous processors. Transient and static tolerances are tighter than VRM 8.2.
• Maximum current is increased to 18.4A for flexible motherboard designs.
• Additional motherboard decoupling is required to meet VRM 8.4.
2.2.10. Decoupling Guidelines for Flexible PGA370 Designs
These are preliminary decoupling guidelines for Flexible PGA370 designs and are estimated to meet
VRM 8.4 V1.5 flexible motherboard guidelines (Vcc=1.6V, Icc = 0.8 - ~18.4A).