Internet Explorer 9 system requirements

Computer/Processor

• Computer with a 1 gigahertz (GHz) 32-bit (x86) or 64-bit (x64) processor.

Operating System

• Windows Vista 32-bit with Service Pack 2 (SP2) or higher
• Windows Vista 64-bit with Service Pack 2 (SP2) or higher

• Windows 7 32-bit or higher
• Windows 7 64-bit or higher

• Windows Server 2008 32-bit with Service Pack 2 (SP2) or higher
• Windows Server 2008 64-bit with Service Pack 2 (SP2) or higher

• Windows Server 2008 R2 64-bit

Memory

• Windows Vista 32-bit – 512 megabytes (MB)
• Windows Vista 64-bit – 512 MB

• Windows 7 32-bit – 512 MB
• Windows 7 64-bit – 512 MB

• Windows Server 2008 32-bit – 512 MB
• Windows Server 2008 64-bit – 512 MB

• Windows Server 2008 R2 64-bit – 512 MB

Hard Drive Space

• Windows Vista 32-bit – 70 MB
• Windows Vista 64-bit – 120 MB

• Windows 7 32-bit – 70 MB
• Windows 7 64-bit – 120 MB

• Windows Server 2008 32-bit – 150 MB
• Windows Server 2008 64-bit – 200 MB

• Windows Server 2008 R2 64-bit – 200 MB

Drive

• CD-ROM drive (if installation is done from a CD-ROM)

Display

• Super VGA (800 x 600) or higher-resolution monitor with 256 colors

Peripherals

• Modem or Internet connection
• Microsoft Mouse, Microsoft IntelliMouse, or compatible pointing device

 Source