Asus B85M-K User manual

Motherboard
B85M-K

ii
E8698
First Edition
October 2013
Copyright © 2013 ASUSTeK COMPUTER INC. All Rights Reserved.
No part of this manual, including the products and software described in it, may be reproduced,
transmitted, transcribed, stored in a retrieval system, or translated into any language in any form or by any
means, except documentation kept by the purchaser for backup purposes, without the express written
permission of ASUSTeK COMPUTER INC. (“ASUS”).
Product warranty or service will not be extended if: (1) the product is repaired, modied or altered, unless
such repair, modication of alteration is authorized in writing by ASUS; or (2) the serial number of the
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OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OR CONDITIONS OF
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under the Lesser General Public License Version (“LGPL”) and/or other Free Open Source Software
Licenses. Such software in this product is distributed without any warranty to the extent permitted by the
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Where the applicable license entitles you to the source code of such software and/or other additional data,
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or
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In your request please provide the name, model number and version, as stated in the About Box of the
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the product and describing the problem (please DO NOT send large attachments such as source code
archives, etc. to this email address).

iii
Contents
Safety information...................................................................................................... iv
About this guide......................................................................................................... iv
Package contents....................................................................................................... vi
B85M-K specications summary.............................................................................. vi
Product introduction
1.1 Before you proceed...................................................................................... 1-1
1.2 Motherboard overview ................................................................................. 1-1
1.3 Central Processing Unit (CPU).................................................................... 1-4
1.4 System memory............................................................................................ 1-7
1.5 Expansion slots ............................................................................................ 1-9
1.6 Jumpers....................................................................................................... 1-11
1.7 Connectors.................................................................................................. 1-13
1.8 Onboard LEDs ............................................................................................ 1-20
1.9 Software support ........................................................................................ 1-21
BIOS information
2.1 Managing and updating your BIOS............................................................. 2-1
2.2 BIOS setup program..................................................................................... 2-5
2.3 Main menu..................................................................................................... 2-9
2.4 Ai Tweaker menu ........................................................................................2-10
2.5 Advanced menu.......................................................................................... 2-11
2.6 Monitor menu.............................................................................................. 2-12
2.7 Boot menu................................................................................................... 2-13
2.8 Tools menu.................................................................................................. 2-14
2.9 Exit menu ....................................................................................................2-14
Appendices
Notices ..................................................................................................................... A-1
ASUS contact information...................................................................................... A-3

iv
Safety information
Electrical safety
To prevent electrical shock hazard, disconnect the power cable from the electrical outlet
before relocating the system.
When adding or removing devices to or from the system, ensure that the power cables
for the devices are unplugged before the signal cables are connected. If possible,
disconnect all power cables from the existing system before you add a device.
Before connecting or removing signal cables from the motherboard, ensure that all
power cables are unplugged.
Seek professional assistance before using an adapter or extension cord. These devices
could interrupt the grounding circuit.
Ensure that your power supply is set to the correct voltage in your area. If you are not
sure about the voltage of the electrical outlet you are using, contact your local power
company.
If the power supply is broken, do not try to x it by yourself. Contact a qualied service
technician or your retailer.
Operation safety
Before installing the motherboard and adding devices on it, carefully read all the manuals
that came with the package.
Before using the product, ensure all cables are correctly connected and the power
cables are not damaged. If you detect any damage, contact your dealer immediately.
To avoid short circuits, keep paper clips, screws, and staples away from connectors,
slots, sockets and circuitry.
Avoid dust, humidity, and temperature extremes. Do not place the product in any area
where it may become wet.
Place the product on a stable surface.
If you encounter technical problems with the product, contact a qualied service
technician or your retailer.
•
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•
•
•
•
About this guide
This user guide contains the information you need when installing and conguring the
motherboard.
How this guide is organized
This guide contains the following parts:
• Chapter 1: Product introduction
This chapter describes the features of the motherboard and the new technology it
supports.
• Chapter 2: BIOS information
This chapter tells how to change system settings through the BIOS Setup menus.
Detailed descriptions of the BIOS parameters are also provided.

v
Where to nd more information
Refer to the following sources for additional information and for product and software
updates.
1. ASUS websites
The ASUS website provides updated information on ASUS hardware and software
products. Refer to the ASUS contact information.
2. Optional documentation
Your product package may include optional documentation, such as warranty yers,
that may have been added by your dealer. These documents are not part of the
standard package.
Conventions used in this guide
To ensure that you perform certain tasks properly, take note of the following symbols used
throughout this manual.
DANGER/WARNING: Information to prevent injury to yourself when trying to
complete a task.
CAUTION: Information to prevent damage to the components when trying to
complete a task
IMPORTANT: Instructions that you MUST follow to complete a task..
NOTE: Tips and additional information to help you complete a task.
Typography
Bold text Indicates a menu or an item to select.
Italics Used to emphasize a word or a phrase.
<Key> Keys enclosed in the less-than and greater-than sign
means that you must press the enclosed key.
Example: <Enter> means that you must press the Enter or
Return key.
<Key1> + <Key2> + <Key3> If you must press two or more keys simultaneously, the key
names are linked with a plus sign (+).

vi
(continued on the next page)
B85M-K specications summary
CPU LGA1150 socket for Intel®4th Generation CoreTM i7/ i5 / i3, Pentium®and
Celeron®Processors
Supports 22nm CPU
Supports Intel®Turbo Boost Technology 2.0*
*Intel®Turbo Boost Technology 2.0 support depends on the CPU types.
** Refer to www.asus.com for Intel®CPU support list.
Chipset Intel®B85 Express Chipset
Memory 2 x DIMMs, max. 16GB DDR3 1600/1333/1066MHz, non-ECC, unbuffered
memory modules
Dual-channel memory architecture
Supports Intel® Extreme Memory Prole (XMP)
* Hyper DIMM support is subject to the physical characteristics of individual
CPUs. Please refer to Memory QVL for details.
** Refer to www.asus.com for the latest Memory QVL (Qualied Vendors List).
*** Due to Intel®chipset limitations, DDR3 1600MHz and higher memory modules
on XMP mode will run at the maximum transfer rate of DDR3 1600MHz.
Graphics Integrated Graphics Processor - Intel® HD Graphics support
Multi-VGA output support: DVI-D, RGB port
- Supports DVI-D with max. resolution up to 1920 x1200@60Hz
- Supports RGB with max. resolution 1920x1200@60Hz
- Maximum shared memory of 1024MB
Expansion slots 1 x PCI Express 3.0/2.0 x16 slot (at x16 mode, yellow)
2 x PCI Express 2.0 x1 slots
LAN Realtek®RTL8111G Gigabit LAN Controller
Audio Realtek® ALC887 8-Channel High Denition Audio CODEC
- Supports Jack-Detection and Front Panel Jack-Retasking
* Use a chassis with HD audio module in the front panel to support an
8-channel audio output
Storage Intel®B85 Express Chipset:
- 4 x Serial ATA 6.0 Gb/s connectors (yellow)
- 2 x Serial ATA 3.0 Gb/s connectors (dark brown)
- Supports Intel®Rapid Start Technology* and Intel®Smart Connect
Technology*
* These functions will work depending on the CPU installed.
Package contents
Check your motherboard package for the following items.
Motherboard ASUS B85M-K motherboard
Cables 2 x Serial ATA 6.0 Gb/s cables
Accessories 1 x I/O Shield
Application DVD Support DVD
Documentation User Guide
If any of the above items is damaged or missing, contact your retailer.

vii
B85M-K specications summary
USB Intel®B85 Express Chipset
- 4 x USB 3.0/2.0 ports (2 ports at mid-board, 2 ports at the rear panel)
- 6 x USB 2.0/1.1 ports (4 ports at mid-board, 2 ports at the rear panel)
* Supports ASUS USB 3.0 Boost
ASUS unique
features
ASUS Exclusive Features:
- ASUS EPU
- ASUS UEFI BIOS EZ Mode featuring a friendly graphical user interface
- ASUS USB 3.0 Boost
- ASUS AI Charger
- ASUS GPU Boost
- ASUS Network iControl
- ASUS AI Suite 3
- ASUS Anti-surge Protection
- ASUS ESD
ASUS Quiet Thermal Solution
- ASUS Fanless Design: Stylish Heatsink solution
- ASUS Fan Xpert
ASUS Q-Design
- ASUS Q-Slot
ASUS EZ DIY:
- ASUS CrashFree BIOS 3
- ASUS EZ Flash 2
Back Panel I/O
ports
1 x PS/2 keyboard port (purple)
1 x PS/2 mouse port (green)
2 x USB 3.0/2.0 ports
2 x USB 2.0/1.1 ports
1 x DVI port
1 x D-Sub port
1 x LAN (RJ-45) port
3 x Audio jacks support 8-channel audio output
Internal
I/O connectors/
buttons/switches
2 x USB 2.0/1.1 connectors support additional 4 USB 2.0/1.1 ports
1 x USB 3.0/2.0 connectors support additional 2 USB 3.0/2.0 ports
4 x SATA 6.0Gb/s connectors
2 x SATA 3.0Gb/s connectors
1 x CPU fan connector
1 x Chassis fan connector
1 x Front panel audio connector
1 x S/PDIF Out connector
1 x 24-pin EATX power connector
1 x 4-pin EATX 12V power connector
1 x Speaker connector
1 x System panel connector
1 x CLRTC jumper
(continued on the next page)

viii
B85M-K specications summary
Specications are subject to change without notice.
BIOS features 64 Mb Flash ROM, UEFI AMI BIOS, PnP, DMI2.0, WfM 2.0, SM BIOS 2.7,
ACPI 2.0a, Multi-language BIOS, ASUS EZ Flash 2, ASUS CrashFree
BIOS 3, My Favorites, Quick Note, Last Modied Log, F12 PrintScreen, F3
Shortcut functions and ASUS DRAM SPD (Serial Presence Detect) memory
information
Manageability WfM 2.0, DMI 2.0, WOL by PME, PXE
Support DVD Drivers
ASUS utilities
EZ Update
Anti-virus software (OEM version)
Operating System
Support
Windows®8.1
Windows®8
Windows®7
Form factor uATX form factor: 8.9 in x 6.9 in (22.6 cm x 17.5 cm)

ASUS B85M-K 1-1
Product introduction
1
1.1 Before you proceed
Take note of the following precautions before you install motherboard components or change
any motherboard settings.
• Unplug the power cord from the wall socket before touching any component.
• Before handling components, use a grounded wrist strap or touch a safely grounded
object or a metal object, such as the power supply case, to avoid damaging them due
to static electricity.
• Hold components by the edges to avoid touching the ICs on them.
• Whenever you uninstall any component, place it on a grounded antistatic pad or in the
bag that came with the component.
• Before you install or remove any component, ensure that the ATX power supply is
switched off or the power cord is detached from the power supply. Failure to do so
may cause severe damage to the motherboard, peripherals, or components.
1.2 Motherboard overview
Before you install the motherboard, study the conguration of your chassis to ensure that the
motherboard ts into it.
Ensure that you unplug the power cord before installing or removing the motherboard.
Failure to do so can cause you physical injury and damage motherboard components.
1.2.1 Placement direction
When installing the motherboard, ensure that you place it into the chassis in the correct
orientation. The edge with external ports goes to the rear part of the chassis as indicated in
the image below.

1-2 Chapter 1: Product introduction
B85M-K
Place this side towards
the rear of the chassis
1.2.2 Screw holes
Place six screws into the holes indicated by circles to secure the motherboard to the chassis.
Do not overtighten the screws! Doing so can damage the motherboard.

ASUS B85M-K 1-3
1.2.3 Motherboard layout
B85M-K
PCIEX16
PCIEX1_1
PCIEX1_2
SPEAKER
F_PANEL
CLRTC
SPDIF_OUT
PS2_USBPW1-4
USBPW5-10
USB56
USB78
AAFP
ATX12V
EATXPWR
CPU_FAN
CHA_FAN
BATTERY
Super
I/O
ALC
887- VD2
RTL
8111G
ASP
1255
64Mb
BIOS
LGA1150
Intel®
B85
DDR3 DIMM_A1 (64bit, 240-pin module) DDR3 DIMM_B1 (64bit, 240-pin module)
SATA6G_1 SATA6G_2
SATA6G_4SATA6G_3
SATA3G_1 SATA3G_2
AUDIO
KBMS
LAN_USB34
USB3_12
DVIVGA
SB_PWR
USB3_910
17.5cm(6.9in)
2 41 533
22.6cm(8.9in)
2
6
7
8
8
11 10 91214 131516

1-4 Chapter 1: Product introduction
1.3 Central Processing Unit (CPU)
This motherboard comes with a surface mount LGA1150 socket designed for the Intel®4th
generation Core™ i7 / Core™ i5 / Core™ i3, Pentium® and Celeron®processors.
B85M-K
B85M-K CPU socket LGA1150
1.2.4 Layout contents
Unplug all power cables before installing the CPU.
• Upon purchase of the motherboard, ensure that the PnP cap is on the socket and
the socket contacts are not bent. Contact your retailer immediately if the PnP cap
is missing, or if you see any damage to the PnP cap/socket contacts/motherboard
components. ASUS will shoulder the cost of repair only if the damage is shipment/
transit-related.
• Keep the cap after installing the motherboard. ASUS will process Return Merchandise
Authorization (RMA) requests only if the motherboard comes with the cap on the
LGA1150 socket.
• The product warranty does not cover damage to the socket contacts resulting from
incorrect CPU installation/removal, or misplacement/loss/incorrect removal of the PnP
cap.
Connectors/Jumpers/Slots/LED Page
1. Keyboard and USB device wakeup (3-pin PS2_USBPW1~4) 1-12
2. ATX power connectors (24-pin EATXPWR, 4-pin ATX12V) 1-17
3. CPU and chassis fan connectors (4-pin CPU_FAN, 4-pin CHA_FAN) 1-16
4. Intel®LGA1150 CPU socket 1-4
5. DDR3 DIMM slots 1-7
6. Speaker connector (4-pin SPEAKER) 1-17
7. System panel connector (10-1 pin F_PANEL) 1-19
8. Intel®B85 Serial ATA 6.0Gb/s connector (7-pin SATA6G_1~4 [yellow]) 1-18
9. Intel®B85 Serial ATA 3.0Gb/s connector (7-pin SATA3G_1~2 [dark brown]) 1-18
10. USB 3.0 connector (20-1 pin USB3_910) 1-19
11. USB 2.0 connectors (10-1 pin USB78, USB56) 1-16
12. USB device wake-up (3-pin USBPW5~10) 1-12
13. Clear RTC RAM (3-pin CLRTC) 1-11
14. Digital audio connector (4-1 pin SPDIF_OUT) 1-15
15. Front panel audio connector (10-1 pin AAFP) 1-15
16. Onboard LED (SB_PWR) 1-20

ASUS B85M-K 1-5
1.3.1 Installing the CPU
1
23
A
B
A
B
C
45

1-6 Chapter 1: Product introduction
1.3.2 CPU heatsink and fan assembly installation
To install the CPU heatsink and fan assembly
2
B
A
A
B
1
Apply the Thermal Interface Material
to the CPU heatsink and CPU
before you install the heatsink and
fan if necessary.
3 4

ASUS B85M-K 1-7
1.4 System memory
1.4.1 Overview
This motherboard comes with two Double Data Rate 3 (DDR3) Dual Inline Memory Module
(DIMM) sockets. A DDR3 module is notched differently from a DDR or DDR2 module. DO
NOT install a DDR or DDR2 memory module to the DDR3 slot.
Channel Sockets
Channel A DIMM_A1
Channel B DIMM_B1
B85M-K
B85M-K 240-pin DDR3 DIMM sockets
DIMM_A1 DIMM_B1
1.4.2 Memory congurations
You may install 1GB, 2GB, 4GB, and 8GB unbuffered non-ECC DDR3 DIMMs into the DIMM
sockets.
A
B
B
A
To uninstall the CPU heatsink and fan assembly
2
1
According to Intel®CPU spec, DIMM voltage below 1.65V is recommended to protect the
CPU.

1-8 Chapter 1: Product introduction
• You may install varying memory sizes in Channel A and Channel B. The system maps
the total size of the lower-sized channel for the dual-channel conguration. Any excess
memory from the higher-sized channel is then mapped for single-channel operation.
• Due to Intel® chipset limitations, DDR3 1600MHz and higher memory modules on
XMP mode will run at the maximum transfer rate of DDR3 1600MHz.
• Always install DIMMs with the same CAS latency. For optimal compatibility, we
recommend that you install memory modules of the same version or date code (D/C)
from the same vendor. Check with the retailer to get the correct memory modules.
• Due to the memory address limitation on 32-bit Windows®OS, when you install 4GB
or more memory on the motherboard, the actual usable memory for the OS can be
about 3GB or less. For effective use of memory, we recommend that you do any of the
following:
- Use a maximum of 3GB system memory if you are using a 32-bit Windows®OS.
- Install a 64-bit Windows®OS if you want to install 4GB or more on the
motherboard.
• This motherboard does not support DIMMs made up of 512 megabits (Mb) chips or
less.
• Memory modules with memory frequency higher than 2133 MHz and its corresponding
timing or the loaded X.M.P. Prole is not the JEDEC memory standard. The stability
and compatibility of these memory modules depend on the CPU’s capabilities and
other installed devices.
• The maximum 16GB memory capacity can be supported with 8GB or above DIMMs.
ASUS will update the memory QVL once the DIMMs are available in the market.
• The default memory operation frequency is dependent on its Serial Presence Detect
(SPD), which is the standard way of accessing information from a memory module.
Under the default state, some memory modules for overclocking may operate at a
lower frequency than the vendor-marked value.
• For system stability, use a more efcient memory cooling system to support a full
memory load (2 DIMMs) or overclocking condition.
• Refer to www.asus.com for the latest Memory QVL (Qualied Vendors List)
1.4.3 Installing a DIMM
Unplug the power supply before adding or removing DIMMs or other system components.
Failure to do so can cause severe damage to both the motherboard and the components.
1. Press the retaining clips outward to unlock a DIMM socket.
2. Align a DIMM on the socket such that the notch on the DIMM matches the DIMM slot
key on the socket.

ASUS B85M-K 1-9
A DIMM is keyed with a notch so that it ts in only one direction. DO NOT force a DIMM into
a socket in the wrong direction to avoid damaging the DIMM.
3. Firmly insert the DIMM into the socket
until the retaining clips snap back
in place and the DIMM is properly
seated.
1.4.4 Removing a DIMM
To remove a DIMM:
1. Simultaneously press the retaining clips outward to unlock the DIMM.
2. Remove the DIMM from the socket.
Support the DIMM lightly
with your ngers when
pressing the retaining
clips. The DIMM might get
damaged when it ips out
with extra force.
1.5 Expansion slots
In the future, you may need to install expansion cards. The following sub-sections describe
the slots and the expansion cards that they support.
Unplug the power cord before adding or removing expansion cards. Failure to do so may
cause you physical injury and damage motherboard components.
Locked Retaining Clip
3
DIMM notch
1
1
2
Unlocked retaining clip
1
DIMM notch
2
1
DIMM slot key

1-10 Chapter 1: Product introduction
1.5.1 Installing an expansion card
To install an expansion card:
1. Before installing the expansion card, read the documentation that came with it and
make the necessary hardware settings for the card.
2. Remove the system unit cover (if your motherboard is already installed in a chassis).
3. Remove the bracket opposite the slot that you intend to use. Keep the screw for later
use.
4. Align the card connector with the slot and press rmly until the card is completely
seated on the slot.
5. Secure the card to the chassis with the screw you removed earlier.
6. Replace the system cover.
1.5.2 Conguring an expansion card
After installing the expansion card, congure it by adjusting the software settings.
1. Turn on the system and change the necessary BIOS settings, if any. See Chapter 2 for
information on BIOS setup.
2. Assign an IRQ to the card.
3. Install the software drivers for the expansion card.
When using PCI cards on shared slots, ensure that the drivers support “Share IRQ” or that
the cards do not need IRQ assignments. Otherwise, conicts will arise between the two PCI
groups, making the system unstable and the card inoperable.
1.5.3 PCI Express x1 slots
This motherboard supports two PCI Express x1 network cards, SCSI cards, and other cards
that comply with the PCI Express specications.
1.5.4 PCI Express x16 slot
This motherboard supports one PCI Express x16 graphics card that complies with the PCI
Express specications.
IRQ assignments for this motherboard
A B C D E F G H
LAN - - shared - - - - -
PCIE x16 shared - - - - - -
PCIE x1_1 shared - - - - - - -
PCIE x1_2 - shared - - - - - -
Intel PCH SATA Controller - - - shared - - - -
HD Audio - - - - - - shared
USB2.0_1 - - - - - - - shared
USB2.0_2 - - - - shared - - -
USB3.0 - - - - - shared -

ASUS B85M-K 1-11
1.6 Jumpers
1. Clear RTC RAM (3-pin CLRTC)
This jumper allows you to clear the Real Time Clock (RTC) RAM in CMOS. You can
clear the CMOS memory of date, time, and system setup parameters by erasing
the CMOS RTC RAM data. The onboard button cell battery powers the RAM data in
CMOS, which include system setup information such as system passwords.
B85M-K
B85M-K Clear RTC RAM
1 2 2 3
Normal
(Default)
Clear RTC
CLRTC
To erase the RTC RAM:
1. Turn OFF the computer and unplug the power cord.
2. Move the jumper cap from pins 1-2 (default) to pins 2-3. Keep the cap on pins 2-3
for about 5-10 seconds, then move the cap back to pins 1-2.
3. Plug the power cord and turn ON the computer.
4. Hold down the <Del> key during the boot process and enter BIOS setup to re-
enter data.
Except when clearing the RTC RAM, never remove the cap on CLRTC jumper default
position. Removing the cap will cause system boot failure!
• If the steps above do not help, remove the onboard battery and move the jumper
again to clear the CMOS RTC RAM data. After clearing the CMOS, reinstall the
battery.
• You do not need to clear the RTC when the system hangs due to overclocking. For
system failure due to overclocking, use the CPU Parameter Recall (C.P.R.) feature.
Shut down and reboot the system, then the BIOS automatically resets parameter
settings to default values.

1-12 Chapter 1: Product introduction
B85M-K
1 2
2 3
+5V +5VSB
(Default)
B85M-K Keyboard and USB device wake-up
PS2_USBPW1-4
B85M-K
21 2 3
+5V
(Default)
+5VSB
USBPW5~10
B85M-K USB Device Wake Up
3. USB device wake-up (3-pin USBPW5~10)
Set this jumper to +5V to wake up the computer from S1 sleep mode (CPU stopped,
DRAM refreshed, system running in low power mode) using the connected USB
devices. Set to +5VSB to wake up from S3 and S4 sleep modes (no power to CPU,
DRAM in slow refresh, power supply in reduced power mode).
• The USB device wake-up feature requires a power supply that can provide 500mA on
the +5VSB lead for each USB port; otherwise the system would not power up.
• The total current consumed must NOT exceed the power supply capability (+5VSB)
whether under normal conditions or in sleep mode.
2. Keyboard and USB device wake-up (3-pin PS2_KBPW1~4)
This jumper allows you to enable or disable the keyboard wake-up feature. When you
set this jumper to pins 2-3 (+5VSB), you can wake up the computer by pressing a key
on the keyboard. This feature requires an ATX power supply that can supply at least 1A
on the +5VSB lead, and a corresponding setting in the BIOS.