The people at AMD were so impressed by Innovative Silicon's first-generation Z-RAM technology that they decided to license it back in January. Now, almost a year later, AMD has come back for more and purchased a license for ISi's second-gen Z-RAM tech. Z-RAM, or zero capacitor RAM, is a type of capacitor-less embedded memory built on a silicon-on-insulator process. It can achieve significantly higher densities than the embedded SRAM memory typically found in processor caches.
According to EE Times, second-gen Z-RAM is expected to allow chips to store 5Mb (625KB) of data per square millimeter on a 65nm process. Using this technology, a 65nm processor could theoretically pack 10MB of cache in an area of just 16mmÂ². For reference, 65nm Intel Core 2 Duo chips have a die area of 143mmÂ², and going by Intel's die shots, around a third of that area is required to store 4MB of cache. Z-RAM's speed and power consumption are quite enticing, too. The second-gen tech clocks up to 400MHz and can draw as little as 10μW (0.00001W) per MHz.
AMD's plans for the tech are quite clear. In the ISi press release, AMD's Technology Development VP Craig Sander is quoted as saying, "The combination of density, power, and performance coupled with its ability to work with our standard manufacturing processes makes [Z-RAM] an extremely attractive option for use in our future microprocessors."