How do I know that my CPU supports 64bit operating systems under Linux?

Question

How can I find out that my CPU supports 64bit operating systems under Linux, e.g.: Ubuntu, Fedora?

Answer 1

Execute:

grep flags /proc/cpuinfo

Find 'lm' flag. If it's present, it means your CPU is 64bit and it supports 64bit OS. 'lm' stands for long mode.

Alternatively, execute:

grep flags /proc/cpuinfo | grep " lm "

Note the spaces in " lm ". If it gives any output at all, your CPU is 64bit.

Update: You can use the following in terminal too:

lshw -C processor | grep width

This works on Ubuntu, not sure if you need to install additional packages for Fedora.

Answer 2

If your CPU is a 64bit one (x86-64), you can use it with a 64 bit OS.

Here is a list of 64bit CPUs: http://en.wikipedia.org/wiki/64-bit#Current_64-bit_microprocessor_architectures

Answer 3

I think the easiest way is by:

lscpu|grep "CPU op-mode"