In order for Secon Life to run, you computer must have the specifications listed below:

PC Minimum System Requirements:

* Internet Connection: Cable or DSL
* Operating System: Windows XP (Service Pack 2) o OR Windows 2000 (Service Pack 4)
* Computer Processor: 800MHz Pentium III or Athlon, or better
* Computer Memory: 256MB or better
* Video/Graphics Card: o nVidia GeForce 2, GeForce 4mx, or better o OR ATI Radeon 8500, 9250, or better

Mac Minimum System Requirements:

* Internet Connection: Cable or DSL
* Operating System: Mac OS X 10.3.9 or better
* Computer Processor: 1 GHz G4 or better
* Computer Memory: 512MB or better
* Video/Graphics Card: o nVidia GeForce 2, GeForce 4mx, or better o OR ATI Radeon 8500, 9250, or better

However, Linden labs recommends the specifications listed below:

PC Minimum System Recommendations:

* Internet Connection: Cable or DSL
* Computer Processor: 1.6GHz Pentium 4 or Athlon 2000+ or better
* Computer Memory: 512MB or better
* Video/Graphics Card: o nVidia GeForce FX 5600, GeForce 6600, or better o OR ATI Radeon 9600, X600, or better

Mac Minimum System Recommendations:

* Internet Connection: Cable or DSL
* Operating System: Mac OS X 10.4.3 or better
* Computer Processor: 1.25 GHz G4 or better
* Computer Memory: 768MB or better
* Video/Graphics Card: o nVidia GeForce FX 5600, GeForce 6600, or better o OR ATI Radeon 9600, X600, or better

Check out the official site for more details on system requirements.