Asus Crosshair IV Formula - Manual (Page 51)

IRQ assignments for this motherboard
A B C D E F G H
PCIE_X16_1 shared – – – – – – –
PCI_1 – – – – shared – – –
PCIE_X8 / X1_2 – – – –
shared
(X8)
– –
shared
(X1)
PCI_2 – – – – – shared – –
PCIE_X16 / X8_3
shared
(X16/X8)
– – – – – – –
PCIE_X4_4 shared – – – – – – –
USB1 OHCI Controller – – shared – – – – –
USB1 EHCI Controller – shared – – – – – –
USB2 OHCI Controller – – shared – – – – –
USB2 EHCI Controller – shared – – – – – –
USB3 OHCI Controller – – shared – – – – –
USB3 EHCI Controller – shared – – – – – –
SB SATA/AHCI
Controller
– – – shared – – – –
LAN – – – shared – – – –
1394 – – – – – – shared –
Audio shared – – – – – – –
JMicron SATA
Controller
– – – – shared – – –
USB 3.0 – – – shared – – – –
2.5.4 PCI slot
The PCI slot supports cards such as a LAN card, SCSI card, USB card, and other
cards that comply with PCI specifications. Refer to the figure below for the location
of the slot.
2.5.5 PCI Express 2.0 x16 slots
This motherboard has four PCI Express 2.0 x16 slots that support PCI Express
x16 2.0 graphic cards complying with the PCI Express specifications. Refer to the
figure below for the location of the slots.
PCI Express x16_1 slot
PCI slot 2
PCI Express x16_4 slot
PCI Express x16_3 slot
PCI Express x16_2 slot
PCI slot 1
• In single VGA card mode, use first the PCIe 2.0 x16_1 slot for a PCI
Express x16 graphics card to get better performance.
• In CrossFireX™ mode, use the PCIe 2.0 x16_1 (red) and
PCIe 2.0 x16_3 (red) slots for PCI Express x16 graphics cards to get better
performance.
• We recommend that you provide sufficient power when running
CrossFireX™ mode. See page 2-38 for details.
• Connect a chassis fan to the motherboard connector labeled
CHA_FAN1/2/3 when using multiple graphics cards for better thermal
environment.
ROG Crosshair IV Formula 2-25