Maximum RAM allowed 3GB in 32bit. What if I have 4GB?

Hi Elivers!
While I was reading the description of Elive Beta Download on website, I came across with "Max RAM allowed 3GB" for 32-bit machine. Up until now I believe that 32-bit system can support up to 4GB RAM.

So why 3GB, is it possible to run it on machine with 4GB RAM?

Yes, but only 3GB would be usable.

That's mostly just simplifying if I'm correct.

...though this isn't my strong suit, anyone else know more? :smiley:

EDIT: The direct Answer is: Yes, it is possible to run Elive, even without PAE, with 4 GB or more installed. But only a little less than 3GB would be used.

It is because of the address length. 32bit can only address roundabout 2,8 GB (3 GB barrier - Wikipedia)
But there is PAE (Physical Address Extension), as workaround.

But the MMU (Memory Management Unit) need to support it. Look at the manual for your motherboard, or the RAM compatibility list.
If >4GM RAM is supported, you'll just need to install a kernel with PAE support.

Check PAE on CPU Level:
grep -w pae /proc/cpuinfo
Check PAE on kernel level:
uname -r (There should be seen something like '-pae')
Search for supported kernels:
apt search linux-image |grep pae

Some geekness:
grep CONFIG_X86_PAE /lib/modules/$(uname -r)/build/.config

  • grep: search for pattern
  • CONFIG_X86_PAE: searched pattern
  • /lib/modules/$(uname -r)/build/.config: search path
  • $(uname -r): at the moment loaded version
    (Not tested, I'm on a 64bit Debian at the moment)