The cheapest graphics card you can play it on is an NVIDIA GeForce 510. Operator Overload system requirements state that you will need at least 1 GB of RAM. Additionally, the game developers recommend somewhere around 2 GB of RAM in your system. An Intel Pentium 4 2.00GHz CPU is required at a minimum to run Operator Overload. However, the developers recommend a CPU greater or equal to an Intel Pentium 4 3.00GHz to play the game.
Operator Overload will run on PC system with Windows® 7 (32/64-bit)/Vista/XP and upwards. Additionally it has Mac and Linux versions.
Minimum System Requirements
CPU
1.7 GHz Processor or better
RAM
1 GB RAM
OS
OS X version Leopard 10.5.8 and above
Graphics Card
NVIDIA GeForce 8 or higher, ATI X1600 or higher, Intel HD 3000 or higher