From the Steam Store description:

"Five years ago Carl Johnson escaped from the pressures of life in Los Santos, San Andreas... a city tearing itself apart with gang trouble, drugs and corruption. Where filmstars and millionaires do their best to avoid the dealers and gangbangers.

Now, it's the early 90s. Carl's got to go home. His mother has been murdered, his family has fallen apart and his childhood friends are all heading towards disaster.

On his return to the neighborhood, a couple of corrupt cops frame him for homicide. CJ is forced on a journey that takes him across the entire state of San Andreas, to save his family and to take control of the streets."

REQUIREMENTS:

Windows:
MINIMUM:
OS: Microsoft® Windows® 2000/XP
Processor: 1Ghz Pentium III or AMD Athlon Processor
Memory: 256MB of RAM
Graphics: 64MB Video Card (Geforce 3 or better)
Hard Drive: 3.6GB of free hard disk space (minimal install)
Other Requirements: Software installations required including DirectX and Sony DADC SecuROM
Partner Requirements: Please check the terms of service of this site before purchasing this software.
Recommended:
Processor: Intel Pentium 4 or AMD Athlon XP Processor
Memory: 384MB of RAM (the more the better!)
Graphics: 128MB (or greater) Video Card (Geforce 6 Series Recommended)
Hard Drive: 4.7GB of free hard disk space (full install)
Sound Card: DirectX 9 compatible Sound Card (Sound Blaster Auidgy 2 Recommended)

Mac:
OS: Mac OS X Snow Leopard 10.6.8 or higher
Processor: Intel Core 2 Duo Processor or better
Memory: 1GB of RAM
Hard Disk Space: 5.2GB of free hard disk space
Video Card: ATI X1600, NVIDIA 7300GT, Intel X3100 integrated graphics chip, or better
Additional: This game will NOT run on PowerPC (G3/G4/G5) based Mac systems (PowerMac)

Other Requirements; Software installations required including DirectX and Sony DADC SecuROM.