Takeaway: A significant fraction of energy goes into accessing data from memory. In the table above 32 bit DRaM memory access is 6400 times more costly that the least expensive operation - the 32 bit int ADD.

If energy cost is proving to be an issue, it can at times be beneficial to recompute values (if possible) instead of loading them from DRAM, since DRAM access is so expensive (useful in mobile systems where power usage is often limited). If it's not possible to recompute values and the system is using a lot of power due to DRAM access, it may be worth looking into ways to compress the data being read from DRAM. On slide 40, we will see that compressing models can lead to significant decreases in size, which will also likely reduce power usage since DRAM usage will decrease.