Depends massively on what the software is doing, there is still no standardisation on what a self-driving car means.
Nvidia is pushing PX2 but I have a feeling they are too expensive for most cars - don't know the exact price but "a few thousand dollars" was quoted for the Teslas that use them. Some specs - http://wccftech.com/nvidia-drive-px2-pascal-gtc-2016/
At the same time Qualcomm is pushing their much less performant chips for self-driving cars, but at a much lower price point (hundreds of dollars)
Nvidia is pushing PX2 but I have a feeling they are too expensive for most cars - don't know the exact price but "a few thousand dollars" was quoted for the Teslas that use them. Some specs - http://wccftech.com/nvidia-drive-px2-pascal-gtc-2016/
At the same time Qualcomm is pushing their much less performant chips for self-driving cars, but at a much lower price point (hundreds of dollars)