Nvidia on Wednesday said it has completed the acquisition of Ageia, a maker of software tools for video and PC games.

Nvidia, which announced plans this month to buy Ageia, will use the latter company's products in conjunction with CUDA. CUDA is technology that Nvidia provides developers for offloading work from a computer's general-purpose CPU to a separate graphics-processing unit. Support for Ageia's PhysX software and hardware would be added to CUDA for GPU rendering of PhysX-provided special effects.

Ageia has built a niche for itself in gaming by offering technology that handles those elements of a video game that add realism to the overall experience. For example, the technology adds dust and flying debris to explosions, more life-like character motion and interaction, and dense smoke from objects in motion or on fire.

Ageia's PhysX software is used in 140 titles shipping or in development for PCs, Sony Playstation 3, Microsoft Xbox 360, and Nintendo Wii, according to Ageia. There are more than 10,000 registered users of the PhysX software development kit.

CUDA is used in conjunction with Nvidia's GeForce 8800GT GPU, which has 112 processors for handling the heavy computational tasks of graphics-intensive games.

Nvidia competes for the wallets of gamers with Advanced Micro Devices, which entered the market for PC graphics cards in 2006 with the $5.4 billion acquisition of ATI Technologies. AMD last month launched a two-chip graphics card that it hoped would give a lead in price and performance over Nvidia.

The ATI Radeon HD 3870 X2 combines two graphics processors on a single board, giving it nearly double the performance of the single-chip Radeon HD 3870 introduced in November 2007. The product would compete with Nvidia's GeForce 8800 Ultra that starts at $630. The Radeon HD 3870 X2 has a suggested retail price of $449.