Altering clock frequency and/or volt age may (i) reduce system stability and usef ul life
of the system and processor; (ii) cause the processor and other system compo nents to
fail; (iii) cause reductions in system performance; (iv) cause additional he at o r other
damage; and (v) affect system data integrity. Intel has not tested and does not
warranty the operation of the processor beyond its specifications.
WARNING
Altering PC memory frequency and/or voltage may (i) reduce system stability and
useful life of the system, memory and processor; (ii) cause the processor and other
system components to fail; (iii) cause reductions in system performance; (iv) cause
additional heat or other damage; and (v) affect system data integrity. Intel assumes
no responsibility that the memory included, if used with altered clock frequencies
and/or voltages, will be fit for any particular purpose. Check with the memory
manufacturer for warranty and additional details.
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rd
generation Intel® Core™ processor and Intel® Z77 Express Chipset platform may contain design
The 3
defects or errors known as errata which may cause the product to deviate from published specifications.
Current characterized errata are available on request.
Contact your local Intel sales office or your distributor to obtain the latest specifications and before placing
your product order.
Performance tuning of Intel® Desktop Board DZ77GA-70K enables useful gains that
can enhance overall system performance for gaming, video editing, computation,
performance benchmarking, and other uses. Performance tuning can be done using
the board BIOS or the Intel
The Intel Extreme Tuning Utility was developed for the user wanting performance
benefits while minimizing their time and involvement in the tuning process. A brief
introduction to this utility is provided in Sect ion 1.1. Even those not considering use of
the Intel Extreme Tuning Utility for performance tuning will find the system monitoring
and stress testing features included with this software to be useful.
This remainder of this guide focuses on using the BIOS for performance tuning of Intel
Desktop Board DZ77GA-70K. The main performance tuning focus areas include the
®
Intel
Core™ processors and the memory subsystem. The procedures and examples
included in this guide are for reference only a nd may not work in all situations and
system configurations.
The board is designed with a number of enhancements to support performance tuning
while protecting the user from overheating or damaging board components. These
enhancements include:
Fan speed control — the processor and system fan speeds automatically increase
when elevated temperatures are sensed.
Processor thermal protection — the electrical current applied to the processor is
automatically reduced when the thermal protection temperature set point is
reached.
Processor voltage regulator heat sinks — these provide increased cooling capability
to the voltage regulation system components.
Six-phase processor voltage regulator — component stress is reduced since overall
electrical load is distributed among six phases.
Processor voltage regulator thermal protection — the voltage regulator current is
automatically reduced when the thermal protection temperature set point is
reached.
®
Extreme Tuning Utility.
1.1 Intel® Extreme Tuning Utility
The Intel Extreme Tuning Utility software allows performance tuning and monitoring of
critical system parameters in a run-time environment on Intel Desktop Boards using
the Intel
Extreme Tuning Utility is a great tool for monitor ing most Intel desktop board-based
systems and is available for download at
Intel Desktop Board DZ77GA-70K consists of the 3rd generation Intel Core processor
family and the Intel Z77 Express Chipset (the Platform Controller Hub (Inte l Z77
PCH)). The 3rd generation Intel Core processor family integrates the system memory
controller and the PCI Express x16 interface. DDR3 memory is accessed through two
independent memory channels. A system clock that drives all Desktop Board
components is integrated into the Intel Z77 PCH. The Intel Z77 PCH provides support
for a PCI Express x1 interface, a PCI* bus, SATA, USB, and other system interfaces.
The Intel Z77 PCH communicates with the processor via the DMI bus. BIOS
performance tuning controls include processor turbo ratios, the system clock, and
processor and memory voltages. A simplified system block diagram is shown in Figure
3.1 Hardware Considerations for Performance
Tuning
3.1.1 Processor
In addition to Intel Desktop Board DZ77GA-70K, a processor that allows the desired
level of performance tuning by the user is required. Performance tuning capability
with the 3rd generation Intel Core processor family is dependent on the selected
processor. Fully unlocked processor numbers end in the letter “K” and have maximum
performance tuning potential using the system clock and tur bo ratios. All 3rd
generation Intel Core i5 and 3rd generation Core i7 processor numbers that do not end
in the letter “K” are partially unlocked. Partially unlocked processors allow system
clock and limited turbo ratio increases. 3rd generation Intel Core i3 processors do not
have turbo mode capability and therefore allow performance tuning using the system
clock only.
3.1.2 Memory
Memory modules with XMP profiles have pre-programmed optimized performance
settings created by the manufacturer that can be selected in the BIOS. Using XMP
profiles can simplify memory performance tuning. Capability for memory performance
tuning will likely be limited if low speed, low cost DIMMs are being used.
3.1.3 Power Supply
Performance tuning will increase the demand on the system power supply. Lower
wattage power supplies may have insufficient capacity once the load imposed by the
board, graphics card(s), the processor cooler, other system fans, hard drives, CD/DVD
drives, and other accessories are combined. Inadequate power supply capacity will
result in system shutdowns and stability problems when performance tuning is
attempted or later when a performance tuned system is being operated.
For Intel Desktop Board DZ77GA-70K, the power supply should have at least 150
watts of unused capacity to accommodate the typical needs of performance tuned
processor and memory. For more extreme performance, additional capacity beyond
the extra 150 watts will be needed. Additional power supply capacity will also be
needed if a performance tuned graphics card or pair of graphics cards will be included
in the system. Consult the graphics card manufacturer’s specifications to determine
these additional capacity requirements.
Performance tuning results in additional system heat generation. Increased cooling
capability may be required to allow performance tuning and operation of a
performance tuned system while maintaining stab le operation. Considerations for
increasing cooling capability may include, but are not limited to, chassis type, selection
of air or liquid cooling, processor cooler design, memory module design, and overall
system airflow. Extreme performance tuning requires system designs with
increasingly sophisticated cooling capabilities. It is beyond the scope of this guide to
provide detailed recommendations for system cooling.
CAUTION
Cooling induced moisture condensation from refrigerant systems, dry ice, liquid nitrogen or other
uncommon cooling methods will result in risk for electrical shorting and subsequent damage to the
board and/or the system.
3.2 Suggestions for Effective Tuning
Optimal results will occur if tuning efforts are directed appropriately. For example, if
performance improvements with a certain gaming application are desired, then tuning
efforts should be directed at the system resources used by the game. If the game
software has intensive processor computational work, but relatively light demands on
system memory, then focusing performance tuning efforts on memory will not yield
significant improvements.
System resource (processor, memo r y , et c .) utilization can be determined by running
your software application while mon itoring resource usage. Resource usage can be
monitored with the Intel
be able to provide information about system resource utilization with their application.
Video graphics performance increases may be needed to improve the overall
performance of gaming software. The supplier of the graphics card should be
contacted for information about performance tuning the ir hardware. External graphics
tuning is specific to the graphics card manufacturer and cannot be done using either
the Intel Desktop Board DZ77GA-70K BIOS or the Intel Extreme Tuning Utility.
Earlier performance tuning methods where the frequency of the system clock was
increased are now not the most effective means of boosting performance with the
processors in the 3rd generation Intel Core processor family that support turbo mode.
Turbo mode provides “on demand” performance when needed while allowing the
processor to run at a lower frequency with reduced heat generation and improved
efficiency when demand is low. With Intel Desktop Board DZ77GA-70K, Intel suggests
beginning tuning efforts by optimizing turbo mode performance and then utilizing the
system clock for secondary adjustments.
Keeping a written log of performance tuning settings and the results will be extremely
helpful. Your tuning efforts will be much more efficient if you can refer to the log for
settings that you have already tried. If you need to restore BIOS parameters to
something that worked previously, then information recorded in the log will be helpful.
®
Extreme Tuning Utility. Also, your software supplier should
The log will also be convenient for entering parameters if profiles will be setup using
the Intel Extreme Tuning Utility.
The user may have different performance setting profiles that are needed, depending
on the software applications being run. The Intel Desktop Board DZ77GA-70K BIOS
supports a single profile. The user may either go into BIOS and change the
performance settings as needed or utilize the profile storage capability in the Intel
Extreme Tuning Utility. The Extreme Tuning Utility allows various performance profiles
to be loaded and implemented as needed.
3.3 Accessing BIOS Setup
The BIOS setup screen can be accessed at system startup by pressing the F2 key at
the BIOS screen prompt. It is advisable to run the latest BIOS revision to ensure that
performance features are at the highest level of optimization. The latest version BIOS
can be obtained from http://downloadcenter.intel.com. Instructions for loading the
BIOS into the board can also be found at this link.
Before initiating performance tuning, ensure that the BIOS setup defaults have been
loaded by pressing ‘F9’ while in BIOS se tup mode and then pressing ‘F10’ to save
those settings.
Boot Screen Menu
F2 – to Enter BIOS setup
F7 – to update system BIOS
F10 – Boot options menu
NOTE
If you configured your system to boot to RAID or IDE, the F9 key will reset your SATA
configuration to AHCI. If you are not using AHCI, be sure to restore your SATA
configuration prior to pressing F10 to save the settings.
Should performance values be set beyond the point of stable system operation, the
system may exhibit a failure to boot, a blue screen, a system hang or a recovery
screen as described in the sections below. Exceeding the system stability limits is a
normal, expected occurrence during the performance tuning process and there are
multiple reliable and easy to use options for restoring system operation as described in
the following subsections.
3.4.1 Hardware Watchdog Timer
A hardware watchdog timer has been included as part of the board circuitry and is
enabled by default in the BIOS. This timer will automatically enable the board to
startup if unstable system operation or a failure to boot is detected. If the watchdog
timer detects an issue, the screen shown in Figure 3.1 will be displa yed. In addition,
on the DZ77GA-70K boardat the top of the Diagnostic LED bank, a red LED will
illuminate when the Watchdog Timer is activiated. The user can then go into the BIOS
screen and manually reset performance parameters or use the F9 key to reset all BIOS
defaults to restore system stability. This process can be repeated over and over, so if
the user’s parameter changes do not restore system stability, the watchdog timer will
again intervene and allow the user another opportunity to adjust the BIOS settings.
The watchdog timer works in most, but not all cases. If the watchdog timer did not
detect an issue or was disabled by the user, then one of the alternate recovery options
described in Sections 3.4.2 through 3.4.4 can be used.
Figure 3.1. Screen Displayed When the Watchdog Timer
Detects an Issue
3.4.2 Back to BIOS Button
A second recovery option is to use the Back to BIOS button that is located on the
board’s back panel. This button provides a convenient method of invoking the BIOS
setup menu, as shown in Figure 3.2, in a safe, bootable mode without needing to open
the system chassis to access th e BIOS jumper. When the Back to BIOS button is
depressed, both the button and a red LED located on the DZ77GA-70K board
Diagnostic LED bank will illuminate. The F9 key can then be used to restore all BIOS
settings to defaults at this point or specific performance settings can be individually
revised by the user to restore system stability. Additional info rmation regarding this
feature can be found in the Intel Desktop Board DZ77GA-70K Product Guide.
Figure 3.2. Screen Displayed When System is Started With
the Back to BIOS Button Depressed
3.4.3 BIOS Configuration Jumper
A third recovery optio n is to use the BIOS configuration jumper that is provided on the
board to allow the user to force the board to boot to BIOS Setup in a safe mode. The
user will need to open their system chassis to access this jumper. Refer to the Intel Desktop Board DZ77GA-70K Product Guide for additional information on using the
BIOS jumper for resetting purposes.
3.4.4 Remove Power and Reboot
For a system hang, resetting your system or removing, reapplying power and
rebooting will allow the system to initiate a reboot. The watchdog timer, the Back to
BIOS button, the BIOS configuration jumper, or pressing the F2 key at the setup
screen prompt will allow the user to adjust performance settings i n BIOS to restore
system stability.
3.5 Intel Desktop Board DZ77GA-70K Tuning
using Over-Clocking Assistant™
Included in the DZ77GA-70K Visual BIOS™ setup program is an automated method to
over clock using pre-tested built in settings. These settings have been extensively
developed and tested in Intel’s over clocking laboratory and will work with most
system configurations.
The Overclocking Assistant can be found on the home screen of the Visual BIOS setup.
Note the ‘Unlocked’ icon which shows that an Intel K-SKU processor is installed and
over clocking is unlocked and available. Non Intel K-SKU processors are locked and
can not be overclocked.
To increase the processor frequency using the Overclocking Assistant, simply use the
mouse to move the slider until the desired frequency is shown on the main display.
3.6 Intel Desktop Board DZ77GA-70K
Performance Manual Tuning Process
There are various sequences of steps possible for doing board performance tuning.
The approach presented in this guide is a general starting point, but may not be
optimal for all cases.
Performance tuning is an iterative process. The settings made for a parameter may
affect which settings will work for another parameter. For example, increasing the
system clock frequency may require that previous adjustments to the processor turbo
ratios be revised downward to maintain processor stability.
A full processor and memory tuning sequence consists of the steps suggested below.
Depending on your objectives, it may not be necessary to complete all of the steps in
this sequence. More disc ussion about these steps is included in Sections 3.6.1 through
3.6.9. Checking system stability appears frequently during this sequence. This check
ensures that the work done up to that point will provide stable system performance. If
instability is encountered, the source of the problem can be more easily determined if
regular stability checks have been completed.
1. Configure the BIOS for performance tuni ng
2. Set processor voltage and turbo ratios
3. Check stability
4. Increase system clock frequency
5. Check stability
6. Tune memory
7. Check stability
8. Reduce voltage, current, and power
9. Check stability
10. Re-enable dynamic and burst mode (if possible)
It is recommended that non-essential interfaces (such as, onboard audio, USB, LAN,
external SATA, etc.) be disabled when performance tuning to simplify the process.
Once the performance parameters have been optimized, the onboard features can be
re-enabled.
Scroll to “Configuration” > “On-Board Devices” and use the submenus to disable these
features (refer to Figure 3.3).
NOTE
Do not disable the USB port where the keyboard is
connected.
Figure 3.3. System Setup
Performance tuning options are located in the menu section labeled “Performance”.
From the Performance page, proc ess o r tuning options are under the “Processor
Overrides” section shown in Figure 3.4 below. Also see Appendix A for a table
summarizing these settings and their effects. Sections 3.6.1.1 through 3.6.1.8 include
guidelines for setting the processor override parameters.
Two methods are provided for increasing the processor voltage, Processor Voltage
Override and Voltage Offset. Override commands the VR controller to supply a
constant voltage to the processor ignoring SVID requests from the processor. Offset
tells the VR controller to take the voltage requested by the processor and add extra
voltage to it. This way the processor can still control the voltage based on its loading
and power factors, resulting in a better thermal profile for over-clocking.
3.6.1.2 CPU Voltage Override
On the CPU Voltage Override, increase the voltage setting. This needs to be done to
provide the extra voltage to support performance tuning. The amount of voltage
increase needed depends on the amount of performance increase that is desired. This
is something of a trial and error process and the objective is to provide just enough
voltage so the processor can sustain the desired level of performance. Note that high
voltage settings may potentially cause processor damage. Later in the tuning process,
this voltage will be redu ced to the lowest level that provides stability.
3.6.1.3 CPU VReg Droop Control
Set CPU VReg Droop Control to Low V-droop (Performance) if you are attempting to
maximize processor performance. If you are attempting moderate performance
increases, then the Mid or the High V-droop (Power Saving) selection is acceptable.
3.6.1.4 TDC Current Limit Override
Set the TDC Current Limit Override (Amps). The amount of additional processor
current needed depends on the amount of frequency increase being attempted and the
processor workload.The purpose of the TDC current limit is to thermally protect the
processor voltage regulator. If the processor voltage regulator gets too hot, it will
throttle (reduce the frequency of the processor) and greatly diminish performance.
3.6.1.5 Intel® Turbo Boost Technology
Ensure that Intel® Turbo Boost Technology is set to Enable.
3.6.1.6 Burst Mode Power Limit
Set Burst Mode to enable. Disabling burst mode will cause the processor to set the
burst mode to a specified default power limit of the installed processor. Burst mode is
the maximum instantaneous power that the processor is allowed to consume. It is
recommended that this limit be set higher than the sustained mode power limit.
3.6.1.7 Sustained Mode Time
Set Sustained Mode Time in seconds. One second is re commended as an initial
setting. Setting this time too long will exceed the capability of the processor heat sink
and may result in excess processor heating a nd subsequent throttling (frequency
reduction) to reduce the temperature. A longer time interval in sustained mode may
result in a longer time interval out of sustained mode while accumulated processor
heat is being dissipated.
3.6.1.8 Sustained Mode Power Limit
Set the Sustained Mode Power Limit (TDP) for turbo mode. If the average power
during the sustained mode time exceeds this limit, turbo mode will disengage and the
processor will run at the maximum non-turbo ratio. Inadequate cooling may cause the
processor to throttle. You can use the Intel Extreme Tuning Utility monitoring features
to track processor temperature. If the processor temperature increases steadily while
running under load, the processor cooler capability to dissipate heat is being exceeded
and you will need to reduce the TDP power limit to prevent throttling.
3.6.2 Set Multipliers (Turbo Ratios)
NOTE
Only fully unlocked or partially unlocked processors in the 3rd generation Intel Core
processor family allow modifying the multiplier (turbo ratios). See Section 3.1 for
additional details on tuning capability with the various processors.
Set the highest ratio to be used by turbo mode for each of the 1, 2, 3, and 4 core ratio
limits. The ratio mul tiplied by the host clock frequency determines the processor
frequency that will be obtained. Making these settings is a trial and error process. If
ratios are set too high, the processor will be unstable and will not operate. Reducing
the ratios or increasing the CPU Voltage Override (Section 3.6.1.2) and/or the TDC
Current Limit Override (Amps) (Section 3.6.1.4) can be used to restore processor
operation stability.
For the default host clock setting of 100 MHz, Table 3-1 shows the resulting processor
frequency with various multiplier values.
Note: Multiplier values 60 thru 63 are only available with 3rd Generation core i7
processors.
3.6.3 Check Stability
Establishing stability should be done frequently during the performance tuning
process. A good initial check of system stability is to see if the system can boot into
the operating system. If the sys tem ha s become unstable, refer to Section 3.4 for
recovery options.
When the system can successfully boot into the operating system, various software
applications can be used to stress the processor, memory, and other sub-systems.
When processor cores are idle, the Intel Core processors will operate at a reduced
multiplier val ue. While running in the operating syst e m , the application of a h e av y
load will bring all processor cores out of the idle and run them at the multiplier values
selected in the BIOS setup. Heavy loads can be applied by using commonly available
processor and memory stress testing software.
During stress testing, look for erratic software behavior, a b lue screen or a system
hang. Any of these are indications of system instability. Solutions to instability
include revising the performance settings described in the various areas of Section 3.5.
For processor stability issues, revising voltage settings, turbo ratios, system clock
frequency settings or a combination of these changes will be required.
The Intel Extreme Tuning Utility includes processor and memory stress testing
capabilities in addition to allowing the processor temperature to be monitored as
shown in Figure 3.5. Being able to stress test sub-systems like the processor and
memory with relative independence is helpful. This enables you to determine which
sub-system has become unstable so you know which group of performance
parameters to revise. Revising processor parameters will not restore stability if
memory settings are actually causing the instability.
If processor temperature is steadily increasing or processor throttling is occurring
during stress testing then additional tuning or improved cooling is needed.
Once system stability has been established with stress testing software, recheck
system stability using your normal software applications to ensure stab ility.
Figure 3.5. Intel Extreme Tuning Utility System Monitoring Screen
3.6.4 Increase System Clock Frequency
With both the 2nd and 3rd generation Intel Core processor families, the system clock
frequency is limited to modest increases compared to earlier Intel processors. Limited
processor frequency increases can be done by raising the system clock speed and
leaving the turbo ratio multipliers unchanged. Performance tuning using the system
clock should be done to augment processor performance improvements already
obtained using turbo ratios. Note that system clock changes also affect frequency of
other systems, such as memory and PCI-Express in addition to the processor.
System (host) clock frequency changes were made using the BIOS screen shown in
Figure 3.6. The frequency display shows the results of increasing the system clock
setting from 100 MHz to 105 MHz with the resulting processor speed increase from
3.90 GHz to 4.09 GHz (39x105 MHz = 4.09 GHz).
Figure 3.6. BIOS Screen Showing System Clock Frequency
Increased to 105 MHz
24
NOTE
The multipliers for the processor were left unchanged from the default of 39 and only
the host clock frequency was increased. Since the speeds of the other board
subsystems are derived from the host clock, the memory speed will be increased as
well. This increase may require memory setting adjustments to restore stability.
Consult Section 3.6.5 for more information on memory settings.
A wide variety of memory timing parameters can be adjusted in the BIOS setup as
described in the sections below. See Appendix B for a summary description of
memory settings and their effects.
In addition, DIMM socket population will also affect system performance. Intel
Desktop Board DZ77GA-70K has two independent memory channels which are
indicated by blue or black memory DIMM sockets. For best performance, all sockets
should be populated with memory matched by manufacturer, size, speed, and type.
This matching allows the processor to access data across each of the memory channels
concurrently. When installing memory, insert memory in the blue DIMM connectors
first. If more than two memory modules will be installed, install the additional
memory in the black DIMM connectors.
3.6.5.1 XMP Memory Profiles
Although each memory parameter can be modified individually, the easiest method of
optimizing performance is to use memory that supports Extreme Memory Profiles
(XMP). These profiles are pre-programmed by the manufacturer into the memory
module itself and can be selected from the XMP profile list a s shown in Figure 3.7.
These profiles are validated by the manufacturer and are optimized for both
performance and system stability. The listed XMP profiles will vary depending on the
memory being used.
CAUTION
Operating memory at voltages higher than JEDEC approved 1.5 volts may reduce
processor life.
Figure 3.7. Selection of XMP 1600 Profile Using the BIOS Menu
3.6.5.2 Memory Performance Options
The Memory Configuration BIOS page contains all the memory timing options that can
be adjusted.
NOTE
For each of the timings, except the multipliers, lower number settings correspond with
higher performance and potential memory system instability.
Comment [wpm1]: Isn’t it truer to
say it WILL affect the life of the CPU
and extreme voltage will cause the
processor to fail…
Increasing the host clock frequency will increase the memory speed, in addition to the
processor frequency. Note that the memory is not run directly from the host clock.
The memory clock frequency is generated by the processor using input from the host
clock signal received from the Intel Z77 PCH. The default memory clock frequency
runs at 133.3 MHz. Increasing the system clock frequency affects the memory
frequency according to the following formula:
Memory frequency = (memory multiplier) * (percent increase in host clock) *
(133.3 MHz)
Example: If the host clock frequency was increased by 1% and a multiplier of 8 was
being used then the new memory frequency would be (8) * (1.01) * (133.3 MHz) =
1077 MHz
For the default 133.3 MHz memory clock, the resulting memory frequency with various
multipliers is shown in Table 3-2.
Table 3-2. Resulting Memory Frequency Values for Various Multipl ie rs
Multiplier Resulting Memory Frequency (MHz)
8 1066
10 1333
12 1600
14 1866
16 2133
18 2400
3.6.5.4 Going Beyond XMP Profiles
Using XMP profiles provides much of the obtainable memory performance benefit with
minimum effort. Further increases in memory performance can be obtained by setting
the tCL, tRCD, tRP, and tRAS parameters to their maximum values and increasing the
system clock in small increments while checking system stability between each clock
increase until the system becomes unstable. Note that system clock changes will also
affect the processor frequency and iterative adjustments between clock settings that
work for memory and processor performance parameter settings will be needed if
processor instability occurs.
Once the point of memory instability has been reached with system clock increases,
reduce the system clock frequency until the memory is once again stable (the board
will boot again). Next, reduce the tCL, tRCD, tRP, and tRAS parameter values until the
system once again becomes unstable, then increase the values by one increment.
3.6.6 Reduce Voltage, Current, and Power
Gradually reduce voltage and power settings that were made in the applicable portions
of Sections 3.6.1.2 through 3.6.1.8 while checking stability. When instability is
encountered, increase the setting(s) as needed to restore stable op eration.
3.6.7 Restore Dynamic Voltage
If possible, re-enable dynamic voltage (Section 3.6.1.1). If more than modest
performance tuning increases have been made, re-enabling dynamic voltage may
result in excess heating and subsequent processor throttling. Leave this setting
disabled if processor throttling is occurring.
3.6.8 Reconfigure the BIOS to Re-enable Interfaces
In the BIOS, re-enable interfaces such as, onboard audio, USB, LAN, external SATA,
etc., that were disabled earlier in Section 3.6.1.
3.6.9 Archive Performance Settings
The Intel Desktop Board DZ77GA-70K BIOS allows storing one set of parameter
settings (profile) at any given time. If several groups of performance settings are
needed by the user, the Intel Extreme Tuning Utility allows storing multiple profiles as
shown in Figure 3.9. Performance parameter settings can be entered into the Intel
Extreme Tuning Utility using Manual mode. Selecting “Profiles” from the left menu
brings up a window that allows the user to enter a profile name where the
performance parameter settings will be stored. These profiles can be invoked by
starting the Intel Extreme Tuning Utility and loading the desired profile. The most
recently loaded profile wi ll remain resident in the BIOS, until changes are made by the
user.
28
Figure 3.9. Using the Intel Extreme Tuning Utility for Storing
Figure 4.1 shows the BIOS settings to achieve a processor speed of 4.5 GHz. The
system clock has been left at the default value of 100 MHz. XMP profiles were used to
obtain a memory speed of 1600 MHz.
Figure 4.1. 4.5 GHz Processor Speed Using Turbo Ratios
4.2 4.72 GHz Processor Speed Using Turbo Ratios
and System Clock Changes
Figure 4.2 shows the BIOS settings to achieve a processor speed of 4.72 GHz. Turbo
ratios of 45 were set for all of the processor cores. The system base clock frequency
has been increased from the default value of 100 MHz to 105 MHz. XMP profiles were
used to obtain a memory speed of 1600 MHz. These settings are shown while running
the CPU Stress Test included with the Intel Extreme Tuning Utility shown in Figure 4.3.
30
Figure 4.2. 4.72 GHz Processor Speed Using Turbo Ratios
CPU Idle State When “Low Power” is selected, the BIOS will report a full range of available Enhanced
Intel® Turbo
Boost
Technology
Burst Mode When Intel Turbo Boost Technology is eng aged, Burst Mode allows improved
Burst Mode
Power Limit
(Watts)
Sustained Mode
Time
Sustained Mode
Power Limit
(Watts)
CPU Turbo
Voltage Offset
Internal PLL This is an advanced setting that will slightly increase the internal CPU PLL Voltage for
Overrides the voltage requested by the processor and allows a user selected CPU Static
Voltage to be applied at all times. This option disables the dynamic voltage control of
the processor.
Defines an offset that will always be applied to the voltage requested by the CPU. The
offset is the difference between the selected voltage and the voltage at power on. For
example, if the selected voltage is 1.3V and the CPU powers on at 1.1V, an offset of
0.2V will always be added to the voltage requested by the CPU.
This field is enabled when an override voltage is selected. CPU Voltage Droop occurs
when the processor is put under load. Selecting an option to decrease the voltage
droop will generally increase processor stability, but may consume more power and
generate heat.
Sets the upper current limit (in amps) that the processor can consume.
Used to lower the maximum non-turbo CP U spee d. Th e maximum allowed value is set
by default and is specific to your processor model.
Intel SpeedStep Technology frequency steps to the operating system. When “High
Performance” is selected, the BIOS will report only the top frequency step. Note: Cstates may impact the ability of some frequency monitoring tools to accura tely report
the full frequency.
Enabling Intel Turbo Boost Technology also enables Enhanced Intel SpeedStep
Technology and automatically allows processor cores to run faster than the base
operating frequency if the core(s) is operating below power, current, and temperature
specification limits.
instantaneous performance beyond what is already provided by Sustained Mode. It is
recommended to leave this ena bl ed for Overclocking as selecting “D i sa b l ed” will cause
the processor to use a default value.
This control is enabled when Bu rst Mo de is e nabled. Burst Mode Power Limit is the
maximum power (in watts) that can be used by the proces sor w hen Turbo Mode is
active. It is recommended that this always be set higher than the Sustained Mode
Power Limit.
Defines a window of time (in seconds) the CPU will use to average th e po w er fo r
comparison to the the Sustained Mode Power Limit.
Defines the maximum sustained power (in watts) as averaged over the Sustained
Mode Time that can be used by the processor when Turbo Mode is activ e. If the
processor exceeds this value, Turbo mode will be disengaged and the maximum nonTurbo ratio will be used until the power level average drops below the limit.
Offset CPU Voltage (in mV) that is only applie d du ri n g Tu r bo Mo d e. N ote : Th is setting
will be ignored if a Static CPU Voltage Ove r ri de is selected.
All multiplier values listed in Table B- are applied to the single 100 MHz (default) host
clock.
Table B-1. Memory Performance Settings
Setup Option Description
Performance
Memory Profiles
Memory
Multiplier
tCL Column address strobe (CAS) Latency: The am oun t of time in cycle s bet ween sen di n g a
tRCD Row address stro be ( RAS) to CAS Delay: The am ou nt of time in cycles f o r is s u i ng an
tRP RAS Precharge Time: This is the minimum time between active commands and the
tRASmin Minimum RAS Active Time: The amount of time between a row being activated by
tRFC RAS Refresh Cycle Timing: This determines the amount of cycles to refresh a row on a
tRRD RAS to RA S Delay: The amount of cycles that it takes to activate the next bank of
tWR Write Recover Time: The amount of cycles that are required after a valid write operation
tWTR Write to Read Delay: The amount of cycles required between a valid write command and
tRTP Contr ols the nu mb er of c lock s that are inserted between a row precharge command an d
Memory Voltage Changes the voltage applied to the memory.
Command Rate The amount of time that commands can be issued.
tRC Determines the minimum number of clock cycles used complete row activation to
tFAW Specifies the time window where four activates are allowed in the same rank.
Automatic setting uses specification compliant values provided by the memory module.
If the memory module supports XMP there will be additional selections for each profile
stored in the module. Selectin g a profile will populate all the settin gs wi t h va lu e s
recommended by the DIMM manufacturer. Selecting Manual Mode after XMP allows the
user to change each of the settings.
Allows selection of memory speed from a list of choices.
read command and the time to act on it.
active command and the read/write commands.
read/writes of the next bank on the memory module.