As the title states, I'm curious to know what differentiates drivers from each other.
I don't understand how the coding that is put into the drivers improves/downgrades the performance of the card.
Right now I'm testing between some drivers for my Nvidia GTX 555M to see which one performs best with battlefield 3. The performance that the newest 314.22 offers is just not good enough. Before I updated from the ~285(the driver which my card came in, I'm not sure of the exact driver, hence the squiggly next to it), the performance was great, apart from the fact that it would completely freeze after about 5-10 minutes of gameplay in battlefield 3. I've noticed a downgrade in games like Dota 2 also on the 314(Dota 2 would not freeze at all on the 285).
Now I'm downloading the 306.97 to see if that is going to perform better, because I have been told it was the best for battlefield 3.
Is it also true that it depends a lot on the graphics card itself? As in, some drivers work well with some cards, but the others don't?
A driver is meant to be the bridge between your operating system (and other software) and your actual video card hardware. So yes, a bad driver can create a bad experience and overall terrible performance.
A bad driver is similar to a bad GPU so it can be difficult to distinguish which is at fault. But a great video card can be made terrible with a bad driver.