This is taken from the Web Site:
http://www.rfactor.net/
Minium
# System Requirements 1.4 GHz processor
# Windows 98 SE, ME, 2000, XP, XP 64-bit (will NOT run in Windows 95 or Windows 98 first edition)
# 512 MB RAM
# Geforce4 4200 or Radeon 9200
# 128 MB video RAM
# DirectX 9.0c
# 2.0 GB of hard drive space for installation
# Internet connection required for one-time activation
Recomended
# Runs Best With Intel Core 2 Duo E6600 processor
# Windows XP
# 2048 MB RAM
# Geforce 7900 GT or Radeon X1900 GT
# 256 MB video RAM
# DirectX 9.0c
# 2.0 GB of hard drive space for installation
# Internet connection required for one-time activation
i best get saving up for a new pc then