7900GTX or higher recommended, although the game will auto configure for the best experience.

Mass Effect screenshot

BioWare Community Manager Jay Watamaniuk has announced the minimum and recommended PC system requirements for the upcoming PC port of Mass Effect. The specs appear pretty reasonable with no dual/quad cores or top end graphics parts necessary. The game will also auto configure promising "an optimal play experience". Auto configured settings can be changed by the user.

Minimum System Requirements for Mass Effect on the PC

Operating System:
Windows XP or Vista

Processor:
2.4+GHZ Intel or 2.0+GHZ AMD

Memory:
1 Gigabyte Ram (XP)
2 Gigabyte Ram (Vista)

Video Card:
NVIDIA GeForce 6 series (6800GT or better)
ATI 1300XT or better (X1550, X1600 Pro and HD2400 are below minimum system requirements)

Hard Drive Space:
12 Gigabytes

Sound Card:
DirectX 9.0c compatible sound card and drivers

Recommended System Requirements for Mass Effect on the PC

Operating System:
Windows XP or Vista

Processor:
2.6+GHZ Intel or 2.4+GHZ AMD

Memory:
2 Gigabyte Ram

Video Card:
NVIDIA GeForce 7900 GTX or higher.
ATI X1800 XL series or higher

Hard Drive Space:
12 Gigabytes

Sound Card:
DirectX 9.0c compatible sound card and drivers - 5.1 sound card recommended

Mass Effect for PC is scheduled for release across Europe on June 6 and you can read exactly why you should be excited about the game here and here.