But mostly you get sick of seeing message,
"3.25GB of 4GB RAM is Usuable" when you go to My Computer.
Only for this unlocking Problem you may decide to Buy a new x64bit Windows.
But you really Don't want to spend these extra few money because Of Microsoft Putting Limitations.
Here is a Small Apps that will Unlock these 4GB Limitations.
Now U can Put upto 64GB of RAM in a x32bit of Windows.
You can download the rampatch by searching in google and various file sharing sites.