Meta's Vistara chip reuses old DDR4 memory to cut server costs

Meta has unveiled its custom Vistara chip, which reuses old DDR4 memory from retired servers to boost new ones, cutting the need for new hardware. The plan was shown at ISCA 2026, with a paper noting servers last 3-5 years but memory can go 7-10 years, saving money amid a global memory shortage.

The Vistara ASIC bridges DDR4 memory to host processors via a PCIe Gen5 x16 interface, supporting up to 256GB per chip. It's used in MemServer devices with an AMD Turin processor and 768GB DDR5 memory, plus 256GB DDR4 through Vistara. Meta says Vistara is now in production across millions of servers for tasks like machine learning and big data, cutting server needs by 25% and latency by 29%.