Compaq 850 LOW Voltage PRODUCTION/DISTRIBUTION, VID0, AGP PWR Rimm, VID1 VID2 VID3 VID4, Vid

Chapter 6 Power and Signal Distribution

6.3.2 LOW VOLTAGE PRODUCTION/DISTRIBUTION

Voltages less than 3.3 VDC including processor core (VccP) voltage are produced through regulator circuitry on the system board.

+5 AUX

+5 VDC

+3.3 VDC

+12 VDC

Power Supply +3.3 VDC

+3 AUX

+5 VDC

+12 VDC

+12.8 Vcpu

VID0

3.3

RIMM Circuit

AGP

PWR

RIMM

Power

Circuitry

Regulator

3.3 VDC	RIMMs
VDDQ (1.5 VDC)
	AGP Bus

2.5 S3 VDC

+1.8 VDC RIMMs

+1.4 Ref

VccP (see text)

Processor

Processor

VID1

VID2

VID3

VID4

Circuit

Figure 6–3.Low Voltage Supply and Distribution Diagram

The VccP regulator produces the VccP (processor core) voltage according to the strapping of signals VID4..0 by the processor. The possible voltages available are listed as follows:

VID 4..0	VccP
00000	2.05 VDC
00001	2.00 VDC
00010	1.95 VDC
00011	1.90 VDC
00100	1.85 VDC
00101	1.80 VDC
00110	1.75 VDC
00111	1.70 VDC
01000	1.65 VDC
01001	1.60 VDC
01010	1.55 VDC

VID 4..0	VccP
01011	1.50 VDC
01100	1.45 VDC
01101	1.40 VDC
01110	1.35 VDC
01111	1.30 VDC
10000	3.50 VDC
10001	3.40 VDC
10010	3.30 VDC
10011	3.20 VDC
10100	3.10 VDC
10101	3.00 VDC

VID 4..0	VccP
10110	2.90 VDC
10111	2.80 VDC
11000	2.70 VDC
11001	2.60 VDC
11010	2.50 VDC
11011	2.40 VDC
11100	2.30 VDC
11101	2.20 VDC
11110	2.10 VDC
11111	No CPU
--	--

6-6Compaq Deskpro EXS and Workstation 300 Personal Computers Featuring the Intel Pentium 4 Processor

First Edition - December 2000