User Guide

ASUS MAXIMUS VIII EXTREME
1-23
Chapter 1
Gray PCIe slot Single VGA SLI/CFX 3-Way CFX 4-Way CFX
PCIE_X16/X8_1
x16 x8 x8 x8
PCIeE_X4_2
- - x4 x4
PCIE_X8/X4_3
- x8 x4 x4
PCIE_X4_4
- - - x4
• We recommend that you provide sufcient power when running CrossFireX™ or SLI
®
mode.
• Connect a chassis fan to the motherboard connector labeled CHA_FAN1-4 when
using multiple graphics cards for better thermal environment.
• New 6th generation Intel
®
Core™ processors support PCIe 3.0 speed rate.
PCIe_x16/x8_1 slot switches to x8 mode when PCIe_x8/x4_3 slot is occupied.
PCIEX4_4 shares bandwidth with SATA6G_56 ports. By default, this slot runs at x2 mode.
To enable x4 mode, please refer to 3.6.9 Onboard Devices Configuration.
IRQ assignments for this motherboard
PCIe 3.0 operating mode
U.2/M.2/SATAEXPRESS1 configuration
U.2, M.2, and SATAExpress1 share bandwidth with priority set to M.2. Refer to the table
below for congurations.
A B C D E F G H
PCIE_X16/X8_1 shared - - - - - - -
PCIE_X4_2 - - shared - - - - -
PCIE_X8/X4_3 - shared - - - - - -
PCIE_X4_4 shared - - - - - - -
I.G.F.X. shared - - - - - - -
Intel Lan Controller shared - - - - - - -
SATA Controller - - - - - - - shared
High Denition Audio shared - - - - - - -
XHCI Controller shared - - - - - - -
Intel Alpine Ridge shared - - - - - - -
ASM1142 shared - - - - - - -
M.2 SATA device
inserted
M.2 PCIe device
inserted
M.2 port empty
U.2
Disabled Disabled Enabled
M.2
M.2 SATA mode M.2 PCIe mode N/A
SATAEXPRESS1
SATA 6G disabled,
PCIe mode enabled
SATA 6G enabled,
PCIe mode enabled
SATA 6G enabled,
PCIe mode enabled