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

**URL:** <https://forum.elivelinux.org/t/maximum-ram-allowed-3gb-in-32bit-what-if-i-have-4gb/2296>\
**Category:** FAQ\
**Tags:** hardware\
**Created:** [June 27, 2020, 4:16pm UTC](https://forum.elivelinux.org/t/maximum-ram-allowed-3gb-in-32bit-what-if-i-have-4gb/2296 "2020-06-27T16:16:12Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![muhibbij](https://forum.elivelinux.org/user_avatar/forum.elivelinux.org/muhibbij/32/1888_2.png) [@muhibbij](https://forum.elivelinux.org/u/muhibbij)\
**Post date:** [June 27, 2020, 4:16pm UTC](https://forum.elivelinux.org/t/maximum-ram-allowed-3gb-in-32bit-what-if-i-have-4gb/2296/1 "2020-06-27T16:16:12Z")

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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?

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**Author:** ![TheTechRobo](https://forum.elivelinux.org/user_avatar/forum.elivelinux.org/thetechrobo/32/3394_2.png) [@TheTechRobo](https://forum.elivelinux.org/u/TheTechRobo)\
**Post date:** [June 27, 2020, 11:24pm UTC](https://forum.elivelinux.org/t/maximum-ram-allowed-3gb-in-32bit-what-if-i-have-4gb/2296/2 "2020-06-27T23:24:38Z")

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> [@muhibbij](#):
>
> is it possible to run it on machine with 4GB RAM?

Yes, but only 3GB would be usable.

> [@muhibbij](#):
>
> Up until now I believe that 32-bit system can support up to 4GB RAM.

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

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

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**Author:** ![LupusE](https://forum.elivelinux.org/user_avatar/forum.elivelinux.org/lupuse/32/319_2.png) [@LupusE](https://forum.elivelinux.org/u/LupusE)\
**Post date:** [June 28, 2020, 6:55am UTC](https://forum.elivelinux.org/t/maximum-ram-allowed-3gb-in-32bit-what-if-i-have-4gb/2296/3 "2020-06-28T06:55:39Z")

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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](https://en.wikipedia.org/wiki/3_GB_barrier))  
But there is PAE ([Physical Address Extension](http://en.wikipedia.org/wiki/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)