TnL is abbreviation. It stands for Transform and Lighting. A transform and lighting video card (which is abbreviated as a TnL video card) is defined as a video card which offers the TnL (or transform and lighting) functionality and hardware support. A transform and lighting video card (which is abbreviated as a TnL video card) is basically a video card which is built in to graphics cards.
Older cards may not run a computer game properly. The reason why some older cards do not run a computer game properly at times is because older cards are not TnL (or transform and lighting) compatible. Some cards, such as the ATI Rage series, Intel, SIS, S3, Matrox, Voodoo, ATI Radeon, Geforce TNT, TNT2, Diamond Viper and Kyro 2 need to be upgraded before you begin to play a computer game, as they do not have the transform and lighting (which is abbreviated as TnL) functionality.
Older cards may not run a computer game properly. The reason why some older cards do not run a computer game properly at times is because older cards are not TnL (or transform and lighting) compatible. Some cards, such as the ATI Rage series, Intel, SIS, S3, Matrox, Voodoo, ATI Radeon, Geforce TNT, TNT2, Diamond Viper and Kyro 2 need to be upgraded before you begin to play a computer game, as they do not have the transform and lighting (which is abbreviated as TnL) functionality.