eDRAM

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Computer memory types
Volatile
DRAM, e.g. DDR SDRAM SRAM Upcoming Z-RAM TTRAM Historical Williams tube Delay line memory
Non-volatile
ROM PROM EAROM EPROM EEPROM Flash memory Upcoming FeRAM MRAM CBRAM PRAM SONOS RRAM Racetrack memory NRAM Historical Drum memory Magnetic core memory Bubble memory Twistor memory

eDRAM stands for "embedded DRAM", a capacitor-based dynamic random access memory usually integrated on the same die or in the same package as the main ASIC or processor, as opposed to external DRAM modules and transistor-based SRAM typically used for caches.

Embedding permits much wider buses and higher operation speeds, and due to much higher density of DRAM in comparison to SRAM, larger amounts of memory can potentially be used. However, the difference in manufacturing processes make on-die integration difficult, so several dies have to be packaged in one chip, raising costs. The latest developments overcome this limitation by using standard CMOS process to manufacture eDRAM, as in 1T-SRAM.

eDRAM is used in many game consoles, including the PlayStation 2, PlayStation Portable, Nintendo GameCube, Wii and Xbox 360.

Both the Cell microprocessor used in the PlayStation 3 and the IBM POWER CPUs will utilize eDRAM for L2 cache, likely in IBM's 45 nm process node.