I just bought a new computer and assembled it myself. After I finished assembling it and installed Windows XP 32-bit, I found that my 4GB of RAM only detected about 2.75GB. I thought that my memory or motherboard was broken. But after I restarted my PC, my BIOS detected my RAM as 4GB. I was a little confused at the beginning.
After I Googled and found some information about it, I found that all 32-bit operating systems have a maximum of 4GB of RAM. Because 2^32 = 4,294,967,296. That’s why the OS with 32-bit version only supports 4GB maximum memory. Even the newest Windows 7 only supports a maximum of 4GB. But the next question is why my PC only detected 2.75GB of RAM. I found that my video card also has 1GB of RAM. So Windows XP will allocate that 1GB from video memory, about 200MB of onboard video memory, and the rest 2.75GB from the RAM.
Is there a way to make Windows XP 32-bit detect more than 4GB of RAM? There were arguments in some forums saying that you can add “/PAE” to the boot.ini so Windows can detect more than 4GB of RAM. But since Windows XP SP2 and SP3, Microsoft doesn’t use “/PAE” config anymore due to compatibility issues with many applications.
So what do I have to do? I should leave it or upgrade to the 64-bit version. But I chose the 32-bit version for now, since not so many applications support 64-bit.
So how about you?