LinuxQuestions.org
Help answer threads with 0 replies.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Software
User Name
Password
Linux - Software This forum is for Software issues.
Having a problem installing a new program? Want to know which application is best for the job? Post your question in this forum.

Notices


Reply
  Search this Thread
Old 03-17-2009, 08:54 PM   #1
kushalkoolwal
Senior Member
 
Registered: Feb 2004
Location: Middle of nowhere
Distribution: Debian Squeeze
Posts: 1,249

Rep: Reputation: 49
How to tell if the system is 32-bit or 64-bit?


Suppose somebody gives you a system without any stickers/label/product information and you are able to boot a 2.6.26 (standard 32-bit) kernel on it. Now if would like to know whether this system supports 64-bit (SMP) kernel or not, how can you find that out?

One way is to install a 64 bit kernel and then try to boot from it.

If machines crashes/hangs => Your system is 32-bit
If machines boots successfully => Your system does support 64-bit

Another way is to go to BIOS and try to see the CPU information.

However is there any other way by which you can tell without installing the 64-bit kernel or going into the BIOS?

Last edited by kushalkoolwal; 03-17-2009 at 08:55 PM.
 
Old 03-17-2009, 08:58 PM   #2
amani
Senior Member
 
Registered: Jul 2006
Location: Kolkata, India
Distribution: Debian 64-bit GNU/Linux, Kubuntu64, Fedora QA, Slackware,
Posts: 2,766

Rep: Reputation: Disabled
dmidecode or lshw from a live 32-bit Linux cd
 
Old 03-17-2009, 08:58 PM   #3
johnsfine
LQ Guru
 
Registered: Dec 2007
Distribution: Centos
Posts: 5,286

Rep: Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194
cat /proc/cpuinfo | grep flags
Then look at the output carefully to see if lm is there.

My output on a system with dual core 64 bit support. Notice the eighth item from the end.
Code:
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall lm pni monitor ds_cpl est cid cx16 xtpr
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall lm pni monitor ds_cpl est cid cx16 xtpr
This thread wrecks my confidence in LQ's "Similar Threads" feature, because this question sure has been asked and answered multiple times before and every item I see in "Similar Threads" is a total miss. I'm still sure a few attempts at searching would have found the correct similar threads. Answering again was easier.

Last edited by johnsfine; 03-17-2009 at 09:07 PM.
 
Old 03-17-2009, 09:01 PM   #4
kushalkoolwal
Senior Member
 
Registered: Feb 2004
Location: Middle of nowhere
Distribution: Debian Squeeze
Posts: 1,249

Original Poster
Rep: Reputation: 49
Quote:
Originally Posted by amani View Post
dmidecode or lshw from a live 32-bit Linux cd
What should I look in the output. Is the following sufficient to conclude that our machine is 64-bit?
Code:
debian:~# dmidecode | grep 64
        Installed Size: 64 KB
        Maximum Size: 64 KB
        Total Width: 64 bits
        Data Width: 64 bits
debian:~#
 
Old 03-17-2009, 09:02 PM   #5
kushalkoolwal
Senior Member
 
Registered: Feb 2004
Location: Middle of nowhere
Distribution: Debian Squeeze
Posts: 1,249

Original Poster
Rep: Reputation: 49
Quote:
Originally Posted by johnsfine View Post
cat /proc/cpuinfo | grep flags
Then look at the output carefully to see if lm is there.

My output on a system with dual core 64 bit support. Notice the eight item from the end.
Code:
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall lm pni monitor ds_cpl est cid cx16 xtpr
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall lm pni monitor ds_cpl est cid cx16 xtpr

Yes my system does have "lm" too. What does it stand for?
 
Old 03-17-2009, 09:08 PM   #6
johnsfine
LQ Guru
 
Registered: Dec 2007
Distribution: Centos
Posts: 5,286

Rep: Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194Reputation: 1194
Quote:
Originally Posted by kushalkoolwal View Post
Yes my system does have "lm" too. What does it stand for?
Long Mode

So your system could run a 64bit kernel.
 
Old 03-17-2009, 09:13 PM   #7
amani
Senior Member
 
Registered: Jul 2006
Location: Kolkata, India
Distribution: Debian 64-bit GNU/Linux, Kubuntu64, Fedora QA, Slackware,
Posts: 2,766

Rep: Reputation: Disabled
'64-bit capable'

you will find it in the CPU info of dmidecode

Last edited by amani; 03-17-2009 at 09:14 PM.
 
Old 03-17-2009, 09:21 PM   #8
kushalkoolwal
Senior Member
 
Registered: Feb 2004
Location: Middle of nowhere
Distribution: Debian Squeeze
Posts: 1,249

Original Poster
Rep: Reputation: 49
Quote:
Originally Posted by amani View Post
'64-bit capable'

you will find it in the CPU info of dmidecode
Not necessarily, here is my dmidecode CPU output on my 64-bit machine:

Code:
debian:~# dmidecode -t 4
# dmidecode 2.9
SMBIOS 2.4 present.

Handle 0x0004, DMI type 4, 35 bytes
Processor Information
        Socket Designation: U2E1
        Type: Central Processor
        Family: Other
        Manufacturer: Intel
        ID: F9 06 00 00 FF FB EB BF
        Version: Genuine Intel(R) CPU             
        Voltage: 3.3 V
        External Clock: Unknown
        Max Speed: 4096 MHz
        Current Speed: 2200 MHz
        Status: Populated, Enabled
        Upgrade: ZIF Socket
        L1 Cache Handle: 0x0005
        L2 Cache Handle: 0x0006
        L3 Cache Handle: Not Provided
        Serial Number: Not Specified
        Asset Tag: Not Specified
        Part Number: Not Specified
debian:~#
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
Has anyone installed a 32-bit debian system to replace their current 64-bit system? BigVig Debian 2 06-27-2008 11:44 AM
LXer: Upgrade from 32-bit to 64-bit Fedora Linux without a system reinstall LXer Syndicated Linux News 0 01-11-2008 10:42 PM
Can I build 32-bit LFS on a 64-bit AMD system? dhave Linux From Scratch 4 07-23-2007 08:00 PM
no sound in 32 bit chroot on 64 bit system <solved> otchie1 Linux - Software 0 11-28-2006 06:03 PM
Getting Konqueror to load 32 bit plugins on a 64 bit system slantoflight Linux - Software 1 05-28-2006 06:17 PM

LinuxQuestions.org > Forums > Linux Forums > Linux - Software

All times are GMT -5. The time now is 10:13 AM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration