What's the difference between "stm32f407vgtx" & "stm32f407vg"

Hi In Software pack there is a "stm32f407vgtx" micro and in legacy packs there is "stm32f407vg". I have a Discovery board that I bought about 4 years ago that has stm32f407vg micro on it. So Which one...
What's the difference between "stm32f407vgtx" & "stm32f407vg"

Hi In Software pack there is a "stm32f407vgtx" micro and in legacy packs there is "stm32f407vg". I have a Discovery board that I bought about 4 years ago that has stm32f407vg micro on it. So Which one...