SRAM can potentially use very little power on modern processes, depending on how fast you want to be able to access it. If you are just making a relatively low

SRAM can potentially use very little power on modern processes, depending on how fast you want to be able to access it. If you are just making a relatively low-speed L3, getting rid of the heat produced in the SRAM itself will never be a problem. In general, the problem in SRAM layered on chip is considered to be that the stacked dies are a very good insulator, so the hot active die on the bottom will have heat dissipation problems.