According to Microsoft, a Windows XP installation requires at least 1.5GB of hard-drive space. However, your computer may get a few hundred MB of that space back after the installation completes. The extra space is used to copy and decompress the installation files during the installation process.

Can Windows XP use more than 4GB of RAM?

You can have a lot more RAM in Windows XP, but only so much is available to each process. The actual system-wide limit in XP is 4GB, not 3.25GB. You can easily exceed 3.25GB RAM in 32bit XP by simply swapping in a video card with less RAM (you’re probably running a 768MB card right now).

What is the maximum hard drive size for Windows XP?

Hard Disk Drives Capacity Limits