Ubuntu – Can Ubuntu use all the 4GB of RAM


I have a dell laptop with 4GB of ram and 500GB of storage.I just finished installing windows 8.1 32bit version, which utilizes 3GB of ram.

Can I install and run Ubuntu to utilize that unusable portion of Ram.Then how?
Thanks in advance

Best Answer

First: 3GB is the maximum usable memory the 32-bit version can handle

There are exceptions, such as 32 bit Ubuntu with PAE. But in general if you have 4GB or more RAM you should use a 64 bit operating system.

Second: There can be only one operating system running your PC at any one time.

Think of this as having one car and two drivers. Only one driver can drive the car at a time. You have to stop the car if you want to switch drivers. Similarly, you have to stop the PC if you want to switch between Windows and Ubuntu.

An Example of 1 car and 2 drivers continued

Suppose there are two drivers A and B in a car. Driver A is driving, on a road with speed limit of 40. But driver A can only drive at 30. Driver A is like 32 bit Windows (or 32 bit (non-PAE) Ubuntu). There is unused speed of 10. The driver B, who is sitting in the same car cannot use that unused speed. You have to stop the car and let Driver B drive. When you let Driver B drive, whether she will use the full speed of 40 or not will depend on what kind of driver she is.

In conclusion: Can Ubuntu use all my 4GB of RAM?

Yes! All currently supported 32 bit versions of Ubuntu are PAE enabled. So irrespective of the 32 bit or 64 bit versions of Ubuntu you choose, it will support all of your 4GB RAM. See What are the differences between 32-bit and 64-bit, and which should I choose? for more on which Ubuntu you should choose. I hope this helps

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