Bios power: Power Management Settings — BIOS for Beginners

Power Management Settings — BIOS for Beginners

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This area of the BIOS seems to be the most misunderstood. When these settings are not properly configured, the result can be systems that do not shut down correctly, or that enter or awaken from the Standby or Hibernate modes improperly. Since Windows has built-in power management, you’ll want to disable all power management in the BIOS. Otherwise, the two fight with each other, and neither works properly. Motherboard manufacturers don’t assume that everyone is using Windows, so many of these settings exist for non-Windows users.

ACPI Suspend to RAM : ACPI stands for Advanced Configuration and Power Interface — not to be confused with APIC or IPCA, which some people may find as options in their BIOS setup programs. The Suspend to RAM feature, sometimes referred to as S3/STR, lets the PC save more power when in Standby mode, but all devices within or attached to the computer must be ACPI-compliant. Some BIOS’s offer an S1/POS option for this scenario. If you enable this feature and experience problems with the standby mode, simply go back into the BIOS and disable it.

Video Off Method : The DPMS (Display Power Management System) option allows the BIOS to control the video display card if it supports the DPMS feature. The Blank Screen option simply blanks the screen — use this for monitors without either power-management or «green» features. The V/H SYNC Blank option blanks the screen and turns off vertical and horizontal scanning. If your computer and monitor were built within the last four years, I recommend setting this to DPMS.

HDD Down In Suspend : This feature determines whether the hard-disk drive is automatically shut down when the computer enters Suspend mode. While most power settings of this type are controlled within Windows, if you find the hard drive is not powering down when the computer enters Suspend mode — assuming your computer even allows Suspend and Hibernate modes — then enable this option. Otherwise, the recommended setting is Disabled.

PWR Button < 4 Secs : By default, all ATX computers will power off after the power button is held for more than four seconds. This setting tells the computer what to do if the power button is held down for less than four seconds. The options are to power off the system or enter Suspend mode. This setting is up to you.

Power Up On PCI Device : If you use Wake-On-LAN — typically employed in large office environments to turn on computers for remote administration — you will want this setting Enabled. Otherwise, I recommend you set it to Disabled.

Wake/Power Up on Ext. Modem : This setting tells the computer to turn itself on when a phone line plugged into its modem rings. Once again, this is used for remote administration. For other environments — in other words, most users — I recommend you set this to Disabled.

Automatic Power Up : This feature, if enabled, lets you designate a specific time each day when the PC will turn itself on. If that’s useful to you, set it to Enabled. Otherwise, I recommend Disabled.

Time (hh:mm:ss) of Alarm : This field sets the time for automatic power-up, based on a military/24-hour clock. The Automatic Power Up field must be enabled to use this feature.

AC Power Loss Restart : This option lets you tell the PC what to do when power is restored after an unexpected loss of power. Disabled leaves the system off, while Enabled reboots the system. Previous State sets the system back to the state it was in before the power interruption. I recommend you set this to Disabled.

Power On By PS/2 Mouse : When enabled, this feature allows the use of a PS/2 (not USB) mouse to turn on the system. Disabled is recommended, so you don’t accidentally keep turning on your computer.

Power On By PS/2 Keyboard : When enabled, this feature lets specific keys on a PS/2 keyboard be used to turn on the system. Disabled is recommended, as most people find this of an annoyance when they accidentally press the wrong key.

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Power Management Settings

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Power management settings in Windows 10 (and BIOS)

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I always found the power management settings and energy saving options very confusing since there are more than one.

The first one being the dialog you can open from your taskbar. There is no information at all what those profiles do and how they affect performance, display brighness, etc.:

Also, there is this next window. Where weirdly enough I can’t select the three profiles from the taskbar, but one. Does this mean is is not related to the profiles in the taskbar at all?

Now it gets really confusing as I can modify the profiles from the previous dialog to be more specific. Here I can set when to power off the monitor or even how much CPU-Performance I want.

So now I wonder, what happens if I set my CPU-Performance to max and my profile in the taskbar to the lowest setting? What wins? Does it affect one another? And why is it so hard to find information on this? It feels so basic.

Bonus points if someone can to me explain how this is also all affected by the BIOS settings. If my BIOS-settings are wrong, can it be that 100% performance, is not really 100%?

Of course there are also settings in the driver of my laptop’s manufacturer. But I’ll skip that for now.

Thank you so so much.

• windows
• windows-10
• bios
• power-management
• energy-saving

1

There is not much overlap here between the BIOS and Windows as regarding performance.

The setting you see in the BIOS is only for turning on/off the CPU option of the
Enhanced Intel Speedstep® Technology.

This technology is built into the CPU, not under the control of the OS,
and it allows the CPU more freedom when dynamically adjusting
processor voltage and core frequency.
Its aim is to decrease average power consumption and heat production
by allowing faster and finer control of the performance parameters.

With or without Speedstep, the CPU will adjust automatically its performance,
if it supports boost (and its opposite).
This technology is only advertised as giving faster response time so the CPU
will detect states of less/more usage faster and so will lower/increase its power
consumption faster.
It should be more of importance to large computer centers where power is costly.

4

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Setting the Setup BIOS to Maximum Performance

Introduction

It is well known that the performance of your motherboard is highly dependent on the temporary memory settings made in the BIOS Setup. The name of the Setup items in which these temporary parameters are set may vary depending on the chipset and BIOS on your motherboard. Different BIOSes offer the user a different set of options for customizing your system: some (such as Award or AMI) have more than enough options, while others (such as Phoenix) do not provide such options at all. Generally speaking, to achieve maximum performance, you should strive to reduce all time delays. However, setting too small values ​​that are not supported by your system can lead to instability, freezes and inability to boot the computer. However, one should not despair. It is enough to load the Setup defaults after re-entering Setup, and you can be sure that your system will return to its original state. Changing Setup settings cannot damage your system. But the default settings will not provide maximum performance.

This document does not cover the basic issues of interaction with the Setup BIOS, information about which can be found in the documentation for your motherboard. Here is how to overclock your computer without opening the case.

Advanced Chipset Setup

Everything related to time delays and described below can be found in the Advanced Chipset Setup section of your BIOS Setup. The options in this section that affect the performance of your computer are described below.

Auto Configuration

If you want to make any changes to the settings, this option must be disabled. Enabling it leads to the installation of all default time delays, which, as you already know, do not provide maximum performance.

DRAM Read Timing

Keep in mind that the algorithms of the modern Pipeline Burst Cache are designed in such a way that it is much more profitable to perform memory exchanges not in words or bytes, but in groups of four or eight consecutive double words. In terms of timing diagrams, the delay in a memory exchange of several double words looks like x-y-y-y for normal access and x-y-y-y-z-y-y-y for write-back access. Here, the first digit indicates the number of processor cycles required to read the first double word, and the remaining numbers indicate the number of processor cycles required to read subsequent double words. For example, for Pipeline Burst Cache RAM it looks like 3-1-1-1 or 3-1-1-1-1-1-1-1. For conventional main memory, these numbers are not rigidly defined and may vary depending on its type and speed, as well as the advanced user. Therefore, you can use BIOS Setup to change the x, y and sometimes z parameters to increase the performance of the memory subsystem. This suggests the conclusion that in order for the processor to operate faster with memory, you must reduce the above values. Valid values ​​for memory cycles are x222 or x333 for EDO RAM, x333 or x444 for FPM RAM, and x111 or x222 for SDRAM. It is these values ​​that you can change in your Setup. You may have already guessed that SDRAM is the fastest type of memory.

Reduce the waiting times! This will speed up your work. However, keep in mind that when reducing the settings, you should check the stability of the system under multitasking operating systems (for example, Windows 95). Moreover, this check is best performed when actively working with memory. For example, I run two copies of Quake under Windows 95 and switch intensively between them for a while. If everything works, then congratulations.

DRAM Write Timing

This option, which is responsible for the time of writing to memory, is set similarly to the previous one. The only difference to keep in mind is that the latency values ​​for EDO and FPM are set to the same, since the speed of accessing these types of memory differs only when reading (EDO is faster).

As in the previous case, set the smallest possible values. But at the same time, the system must work!

RAS to CAS Delay

It’s rather difficult to make a sensible explanation about this, since the size of my page is limited by the provider.

However, similarly, try to reduce this value, but keep in mind that not all types of memory will work with them. Therefore, do not forget to check the performance of the system in this case as well.

DRAM Leadoff Timing

In short, this is the «x» that was mentioned page back (read/write timing). But setting this value makes a difference between existing chipsets. For example, the maximum that Triton FX can read is 7-y-y-y, while Triton TX or HX allows you to set 5-y-y-y. Therefore, the latest chipsets will run faster. When recording, FX allows you to set 5-y-y-y, and HX and TX can work at 4-y-y-y, but Intel recommends these settings only at an external frequency of 50 or 60 MHz.

As you may have guessed, it is better to set the lowest possible value and check if it works. But the system will only work with a value of 5 if you use memory with an access time of 50ns (or faster) for EDO or 10ns for SDRAM.

Turbo Read Leadoff

Changing this value allows «x» to be further reduced. But the memory that would support this option is quite rare.

You can of course try to enable this setting, but be aware that your system is unlikely to run smoothly, if at all. But if you are lucky, then do not forget to carefully check the performance.

Turbo Read Pipelining

It appears that changing this option changes the «z» in the timing diagram above.

If you want your computer to run fast, try enabling this option as well, although you cannot be sure that the system will run at all.

Speculative Lead Off

When this option is enabled, the DRAM controller may start reading before the address where the requested data is located is completely decoded. This can even speed up memory handling. If this is not the case, then all questions to Novations Technologies Inc.,

Whatever it is, system performance is improved when this option is enabled.

 stress-ng --cpu 40 --cpu-method matrixprod --metrics --timeout 60 

 stress-ng --cpu 40 --io 4 --vm 1 --vm-bytes 128G --timeout 60s --metrics-brief 

 stress-ng --cpu 40 --io 4 --vm 1 --vm-bytes 128G --timeout 30m 

 stress-ng --sequential 0 --class io --timeout 60s --metrics-brief