I recently purchase a new Graphics card. I had the choice between
GeForce GTX 560 Ti (Fermi) 1GB 256-bit GDDR5 PCI Express 2.0 x16 HDCP
GeForce GTX 560 Ti (Fermi) 2GB 256-bit GDDR5 PCI Express 2.0 x16 HDCP
I choose the 2GB but to be honest I have know Idea how or if i will notice the difference.
Can someone explain to me what that extra 1GB will do for me?
Provide improved visual experience at high resolutions / with high video memory demanding games.
Example if you have 2 monitors with 2500 x 1600 resolution, you might find huge difference between 1GB and 2GB GPU as you go higher in graphic settings.
Generally speaking the 1gb is not going to cause any issues on a single 1920x1080 (or 1200) monitor, and less so on lower resolution. Also with a single 560 Ti, your GPU power will probably be a limiting factor much before the VRAM.
As perfectblue said, very large resolutions can eat up a lot more VRAM. They also require a lot more GPU power, but that VRAM can make a much more noticeable difference.
I would say the 2GB card is alright for being more "future proof" but it's not really necessary.