X-bit labs

Advanced Micro Devices Intends to Increase Cache Sizes.

Category: CPU

by Anton Shilov

[ 01/19/2006 | 09:55 AM ]

Advanced Micro Devices, the world’s second largest maker of microprocessors, has singed an agreement with Innovative Silicon Inc., a startup that has developed zero-capacitor memory (Z-RAM) technology that allows to increase processor caches by up to five times without increasing the size of the die.

“The dramatic increase in density offered by ISi’s Z-RAM embedded memory can enable much larger on-chip microprocessor cache memories resulting in improved performance and reduced I/O power consumption,” said Craig Sander, corporate vice president of technology development at AMD, EETimes web-site reports.

The Z-RAM technologi is capacitor-less, single transistor DRAM harnessing the floating body effect of Silicon on Insulator (SOI) devices. This technology is capable of achieving twice the memory density of existing embedded DRAM technology and five times that of SRAM, which is used for processor caches, yet requires no special materials or extra mask/process steps. The Z-RAM technology requires silicon-on-insulator process technology and thus will suit for AMD’s central processing units (CPUs).

“We’ve looked at data from Innovative Silicon and it looks very promising. We still need to assure ourselves that this will work in our own application. We need to see how it scales and we need to make our own test vehicles,” Mr. Sander is reported to have said. It is expected that AMD will test the technology at its 65nm and 90nm nodes located in its Fab 30 and Fab 36, Dresden, Germany.

Advanced Micro Devices traditionally has been behind Intel Corp., the world’s largest maker of microprocessors, when it comes to large on-die caches. Even now loads of microprocessors from AMD have less than 1MB of cache, whereas Intel Corp. supplies chips that integrate more than 4MB of cache to the desktop market. In server space AMD’s chips sport a little bit more than 2MB of cache, whereas Intel commercially ships processors with more than 8MB which significantly boosts performance in multi-threaded applications.

The new technology should allow AMD not only to increase the cache sizes of its processors, but also to offer a very significant performance advantage over competing solutions, as, depending on the application, AMD-based computers outperform Intel-based systems in a lot of cases.

It is unclear when AMD will be in position to use Z-RAM technology.