Windows 7 Forums

Welcome to Windows 7 Forums. Our forum is dedicated to helping you find support and solutions for any problems regarding your Windows 7 PC be it Dell, HP, Acer, Asus or a custom build. We also provide an extensive Windows 7 tutorial section that covers a wide range of tips and tricks.


Windows 7: Processors - Limit Number Used by Windows 7


Processors - Limit Number Used by Windows 7

How to Set the Number of Processors or Cores to be Used by Windows 7
Published by Brink
25 Feb 2010
Published by

How to Set the Number of Processors or Cores to be Used by Windows 7

information   Information
If you have a multiple core processor (CPU) or multiple processors, then this will show you how to limit the number of processors to be used by Windows 7, or to make sure that you are using all processors.

This can be handy for troubleshooting and debugging purposes to be able to determine if there is a problem with a single processor/core, or for a programmer to test their code against a single core while still running on their multi-processor/core system.

Windows 7 uses all of your processors or processor cores by default.
Note   Note
You must be logged in as an administrator to be able to do this.




Here's How:
1. Open the Start Menu, then type msconfig and press enter.

2. If prompted by UAC, then click on Yes.

3. Under the Boot tab in System Configuration, click on the Advanced options button. (see screenshot below)
Name:  Step1.jpg
Views: 32932
Size:  109.8 KB
4. To Have Windows 7 Use All Processors or Cores
A) Uncheck the Number of processors box, and click on OK. (see screenshot below)
NOTE: This is the default setting.
Name:  Default_CPU.jpg
Views: 33307
Size:  63.3 KB
B) Go to step 6.
5. For Windows 7 to Use a Specified Number of Processors or Cores
A) Check the Number of processors box, then select how may processors or cores you want Windows 7 to only be able to use in the drop down arrow menu and click on OK.
Name:  Set_number_of_Processors.jpg
Views: 32821
Size:  60.9 KB
6. Check the Make all boot settings permanent box, and click on OK. (see screenshot below)
NOTE: You will still be able to come back and make changes again if you like.
Name:  Step3.jpg
Views: 32724
Size:  110.9 KB
7. Click on Yes. (see screenshot below)
NOTE: You will still be able to come back and make changes again if you like.
Name:  Step4.jpg
Views: 32402
Size:  68.8 KB
8. Click on the Restart button. (see screenshot below)
WARNING: This will restart the computer immediately. Make sure you save and close anything open that you do not want to lose first.

Tip   Tip
If you checked the Don't show this message again box and would like to restore this Restart box to display again, then see: How to Restore the System Configuration Restart Prompt in Vista or Windows 7
Name:  Step5.jpg
Views: 32527
Size:  26.0 KB
9. When Windows 7 is finished restarting, it will now be using only the number of processors or cores that you specified.
NOTE: You can look in Task Manager (CTRL+SHIFT+ESC) to confirm this number of processors or cores. You will have one graph per core in the CPU Usage History area.
Name:  Task_Manager.jpg
Views: 32596
Size:  158.3 KB
That's it,
Shawn





25 Feb 2010   #1
whs
Microsoft MVP

Vista, Windows7, Mint Mate, Zorin, Windows 8
 
 

As far as I understand, this setting is not really doing anything for you. The setting is only there for some testing purposes. But I may be wrong.


My System SpecsSystem Spec
25 Feb 2010   #2
Brink
Microsoft MVP

64-bit Windows 10 Pro
 
 

Hello Wolfgang,

Yes, it's only for testing purposes for troubleshooting and debugging to be able to determine if there is a problem with a single processor/core, or for a programmer to test their code against a single core while still running on their multi-processor/core system.

I also added it for reference just in case someone used this option and forgot about it, and is wondering why not all of the processor cores are being used.
My System SpecsSystem Spec
25 Feb 2010   #3
whs
Microsoft MVP

Vista, Windows7, Mint Mate, Zorin, Windows 8
 
 

Good, that clarification is useful. I posted my comment because I have seen guys thinking that it would speed up their system - which, of course, it does not.
My System SpecsSystem Spec
.

25 Feb 2010   #4
Brink
Microsoft MVP

64-bit Windows 10 Pro
 
 

LOL, yeah I still get people that report to me that they swear that it has improved performance by selecting all processors. I just do not see how though since they are all used by default anyway.
My System SpecsSystem Spec
25 Feb 2010   #5
Staple Head

Windows 7
 
 

where do get that all cores are used by default. this is not the case. when you go to msconfig, boot, advance option and it's default setting for cores being used is 1, that is exactly what it is using. changing it 2 or more depending on you cpu makes windows use more cores. various programs you install may or may not use all cores by default, but win 7 does not.
My System SpecsSystem Spec
25 Feb 2010   #6
whs
Microsoft MVP

Vista, Windows7, Mint Mate, Zorin, Windows 8
 
 

Quote   Quote: Originally Posted by Staple Head View Post
where do get that all cores are used by default. this is not the case. when you go to msconfig, boot, advance option and it's default setting for cores being used is 1, that is exactly what it is using. changing it 2 or more depending on you cpu makes windows use more cores. various programs you install may or may not use all cores by default, but win 7 does not.

Here we go. No core setting will change that if the program is not designed for it. And the windows kernel needs a major revamp in order to use all cores.
My System SpecsSystem Spec
25 Feb 2010   #7
Airbot

Windows 7 Ultimate x64 SP1
 
 

Quote   Quote: Originally Posted by Staple Head View Post
where do get that all cores are used by default. this is not the case. when you go to msconfig, boot, advance option and it's default setting for cores being used is 1, that is exactly what it is using. changing it 2 or more depending on you cpu makes windows use more cores. various programs you install may or may not use all cores by default, but win 7 does not.

Funny, it's using all my cores by default.

-capture.jpg


My System SpecsSystem Spec
25 Feb 2010   #8
Staple Head

Windows 7
 
 

Quote   Quote: Originally Posted by whs View Post
Quote   Quote: Originally Posted by Staple Head View Post
where do get that all cores are used by default. this is not the case. when you go to msconfig, boot, advance option and it's default setting for cores being used is 1, that is exactly what it is using. changing it 2 or more depending on you cpu makes windows use more cores. various programs you install may or may not use all cores by default, but win 7 does not.

Here we go. No core setting will change that if the program is not designed for it. And the windows kernel needs a major revamp in order to use all cores.
what did you mean "here we go"? here we go someone who does not know what they are talking about, or here we go these two lines are my proof? win 7 out of the box when you click on computer it takes about 3 seconds before it list the drives. click on one of the drives and it takes about 3 seconds before it list the contents. when i go in and change the core count to 2 and do the required restart once back in 7 i no longer have this lag accessing my drives and files. i have tested this on a clean install where it was the first thing i changed. i have tested on a clean install where i have installed all of my drivers, software, and performed all of my tweaks then change the core setting. the only time that i actually get rid of this lag is when i change the cores from 1 to 2. nothing else gets rid of the lag.
My System SpecsSystem Spec
25 Feb 2010   #9
whs
Microsoft MVP

Vista, Windows7, Mint Mate, Zorin, Windows 8
 
 

"Here we go" was supposed to mean "here we go starting the discussion". Since you were the first poster after Brink and I had the little exchange of ideas, you started the (very useful) discussion. There is a lot of mystery around the full usage of multi cores and therefore this will help us to better understand it.

PS: your observation/setting is interesting. I never tried that.
My System SpecsSystem Spec
Comment

 Processors - Limit Number Used by Windows 7




Tutorial Tools





Similar help and support threads
Windows 7 Tutorial Category
Excel 15 digit number limit issue
Try this. Type a 16-digit number in a cell, say: 1234567890123456 Then right click the cell and format this as a number, with no decimal places. Your number has just become: 1234567890123450 (note the last digit is now a zero). great stuff. Not. It has effectively corrupted your input...
Microsoft Office
is there a way to increase the number of processors?
If i want to make the VM in 2 x processors, how would i be able to do that?
Virtualization
Changing the number of processors on an Intel i3
Hi! Everyone, I just finished reading a post on processors, and it showed me how to check to see how many processors I have running... Start> run> msconfig> Boot tab> Advance options>. In the upper left corner it shows I have one (1) selected. I can click on the Number of processors box,...
Performance & Maintenance
BSOD after changing number of processors
Hi all. I read somewhere that in order to improve the boot speed you need to go into MSCONFIG->Boot->Advanced Options...-> Tick the number of processors and select the correct number (2 or 4). It didn't improve anything so I went back the unchecked the Number of processors, I then rebooted the...
BSOD Help and Support
Limit on number of external hard drives?
Does Windows 7 have a limit on how many USB external hard drives it will use? We have 5 WD My Book 1TB drives; 4 of them are recognized and work just fine with Windows 7 Home Premium 64 (which we recently did a clean install of to replace Vista Home Premium 64), but the 5th one doesn't show up...
Installation & Setup
MSDN limit on number of keys?
Hi guys whats up. So in MSDN i am trying to DL windows 7 but i just have a question. You guys (MSDN subscribers ) have any idea on how many keys i can generate? because i accidentlly clicked the generate key twice and it gave me two keys :p. Thats not a problem is it? And also can these keys be...
General Discussion

Our Sites

Site Links

About Us

Find Us

Windows 7 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 7" and related materials are trademarks of Microsoft Corp.

Designer Media Ltd

All times are GMT -5. The time now is 17:13.

Twitter Facebook Google+



Windows 7 Forums

Seven Forums Android App Seven Forums IOS App