difference between "ti" and non "ti" cards

[bostonartgallery]

Whether it's a GTX 750 or a GTX 980, I notice some have them have "ti" after the number. What is the significance of that designation?

 

[Bakua]

Basically, it's an 'Ultra' version or 'Pro' version of the base card, always has better performance/shaders than the original.

 

[bostonartgallery]

Basically, it's an 'Ultra' version or 'Pro' version of the base card, always has better performance/shaders than the original.

Thanks for your input!