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19
Chapter 1: Introduction
Figure 1-6. Intel PCH C621 Chipset: System Block Diagram
Note:
This is a general block diagram and may not exactly represent the features on your
motherboard. See the System Specifications appendix for the actual specifications of your
motherboard.
System Block Diagram
SPI
FRONT PANEL
SYSTEM POWER
CTRL
FAN SPEED
#7 USB2.0
PCH
6.0 Gb/S
USB 2.0
USB
#1
#0
SA
TA
#3
#2
Temp Sensor
W83773 at SMBUS
SPI
AST2500
BMC
BMC Boot Flash
DDR4
SLOT 3
5+1 PHASE
205W
DDRIV 2133/2666
P1
P1
P0
VR13
P0
#G-1
DDRIV 2133/2666
#B-1
#A-1
UPI
PC
I-E
X16
DMI3
DMI3
UPI 10.4G /11.2G
5+1 PHASE
205W
VR13
#H-1
#J-1
#K-1
#L-1
#M-1
VCCP1 12v
VCCP0 12v
UPI
PECI:30
PECI:31
SOCKET ID:0
SOCKET ID:1
#C-1
#D-1
#E-1
#F-1
UPI
P2
P2
SLOT 4
PC
I-E
X16
SLOT 1
PC
I-E
X16
SLOT 2
PC
I-E
X16
CPU1 PCIe X16
CPU2 PCIe X16
SLOT 5
PCI-E X16 G3 (RSC-GR-6-X)
PCI-E X16 G3 (RSC-GR-6-X)
PCI-E X16 G3 (RSC-GR-6-X)
PCI-E X16 G3 (RSC-G-A6 or RSC-G-A66-X1)
PCI-E X16 G3
PCI-E X16 G3 with re-driver
AOM-PIO-i2XT
RM
II/
N
CS
I
VG
A
CO
M
P
O
RT
RG
RM
II
Rear IO
riser card
PCI-E X4 G2
#0-3
USB3.0 x2
#0/1 USB2.0
PCI-E X4 G2
#5
ESPI
Debug Card
TPM HEADER
SPI
BIOS
Bus S/W
#3
#2
#1
#1
#2
#3
DMI3
CPU1 PCIe X16
CPU2 PCIe X8
NVME X8
RSC-G-A66
RSC-GN2-A68
Three riser options
PCIex4 or
SATA
M.2
Flexible I/O
6CH
6CH
CPU2
CPU1
CPU1 PCIe X16
CPU2 NVME X8
RSC-GN2-66