Amazon.com Inc.’s cloud-computing unit announced updated versions of its in-house computer chips while also forging closer ties with Nvidia Corp. — dual efforts designed to ensure it can get enough supplies of crucial data-center processors.

New homegrown Graviton4 chips will have as much as 30% better performance than their predecessors, Amazon Web Services said at its annual re:Invent conference in Las Vegas. Computers using the processors will start coming online in the coming months.