Can Ubuntu use all my 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
Solution 1:
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
Solution 2:
There are a couple of questions you should know about:
1. Can Windows and Ubuntu share resources simultaneously
Since both operating systems work independently, they do not share any type of hardware resources since neither depends on the other one. This means that when you boot Windows, you will see how Windows handles the hardware (Including hard drive usage, motherboard usage and optimal memory usage). When you boot Ubuntu it will work with the hardware provided, independent of how Windows used it before. They do not share any hardware capabilities at this level.
2. Can they somehow be force to share resources
So up to this point, you can not make them share the same hardware at the same time, only one of them can use the hardware at a time. What you could do is use virtualbox or any other virtualization technology to emulate either Ubuntu or Windows.
If you virtualize Ubuntu inside Windows, you will still get the 3GB memory limit for the 4 GB real memory you have. This means that Ubuntu can only work with the 3GB Windows can see, making Ubuntu depend on how Windows manages the resources.
If you virtualize Windows inside Ubuntu, you will be able to see the full 4GB of ram and can work with this to assign some of it to the emulated Windows environment.
3. Can they both work in a dual boot way
In relation to the dual boot process, yes you can boot them in dual boot but to make it easier, take into consideration that you need to first install Windows, then follow up with Ubuntu. To make it even easier, do not use a pre-installed Windows 8. For what I can read from your question, you actually installed Windows yourself, so that makes me think (since you also have 32 bit) that you installed Windows without UEFI support.
If this is correct, simply insert the Live CD/USB image of Ubuntu and install it. The boot process will take care to show both systems when you reboot so you can select which one you would like to boot to. But again, remember, both systems work independent of each other, they do not share memory, cpu, motherboard, drivers or any other hardware related feature while booting from one or the other (Except of course if virtualized environments).
4. Does 32 bit Ubuntu detect my whole 4GB of RAM in comparison to Windows 32 bit
There is something important everyone should know about Windows and Ubuntu. On Windows, the system allocates and reserves a specific amount of memory for System Usage or System Reserved. This can vary between 300 MB up to 1.5 GB. This means that when you check the memory available, what you will actually see is the memory you can use with any other application that is not reserved for system only. So for example, if you have 4 GB of RAM, you will only see, assuming Windows reserves 900 MB of RAM, a total of 3.1 GB of "free available memory". Of course you would ask what happened to the rest. The rest of the 900 MB as reserved for system use, this is a way of optimizing and prioritizing which applications and services have better speed and privileges on the system.
With that in mind, another topic you should know is that Windows 32 bit can only read up to 4 GB of RAM. In the case of Ubuntu, the 32 bit version can read up to 64 GB of RAM, this is because of the PAE feature. Apart from this, Ubuntu and Linux in general have a further optimized kernel that can handle much better the 4 GB limit, so it does not use, 900 MB for example, it just needs less than 200 MB (Even less in other versions and distros, getting to a point of only 1 MB or 2 MB).
I will also include further reading that I wrote to help you along the way:
For better performance should I install 32-bit or 64-bit?
Does 32-bit PAE with more than 4GB RAM improve speed?
Does Ubuntu Desktop 32Bit Support more than 4GB Memory with default installation?
What's the maximum amount of RAM I can use on an specific hardware
Installing Ubuntu Alongside a Pre-Installed Windows with UEFI