There used to be a DRAM with build-in SRAM cache called EDRAM (Enhanced DRAM, not to be confused with eDRAM Embedded DRAM). • 2Kbit SRAM Cache Memory for 15ns

There used to be a DRAM with build-in SRAM cache called EDRAM (Enhanced DRAM, not to be confused with eDRAM Embedded DRAM). • 2Kbit SRAM Cache Memory for 15ns Random Reads Within a Page • Fast 4Mbit DRAM Array for 35ns Access to Any New Page • Write Posting Register for 15ns Random Writes and Burst Writes Within a Page (Hit or Miss) • 256-byte Wide DRAM to SRAM Bus for 7.3 Gigabytes/Sec Cache Fill • On-chip Cache Hit/Miss Comparators Maintain Cache Coherency on Writes Afaik only ever manufactured by a single vendor Ramtron https://bitsavers.computerhistory.org/components/ramtron/_dataBooks/1994_Ramtron_Specialty_Memory_Products.pdf https://bitsavers.computerhistory.org/components/ramtron/_da... and only ever used in two products: - Mylex DAC960 RAID controller - Octek HIPPO DCA II 486-33 PC motherboard https://theretroweb.com/motherboards/s/octek-hippo-dca-ii-486-33 https://theretroweb.com/motherboards/s/octek-hippo-dca-ii-48...