Path: utzoo!utgpu!cunews!bnrgate!bigsur!bnr-rsc!mascot@bnr.ca From: mascot@bnr.ca (Scott Mason) Newsgroups: comp.sys.amiga.hardware Subject: Re: Opinions and Cold Hard Facts Requested Summary: Static RAM -> cache, Dynamic RAM -> main memory Keywords: RAM, memory, static, dynamic, SRAM, DRAM, cache Message-ID: <4315@bnr-rsc.UUCP> Date: 10 Apr 91 20:03:07 GMT References: <20457@cbmvax.commodore.com> Sender: news@bnr-rsc.UUCP Organization: Bell-Northern Research, Ottawa, Ontario, Canada Lines: 31 In article daveh@cbmvax.commodore.com (Dave Haynie) writes: >In article erk@americ.UUCP (Erick Parsons) writes: > >> Is static ram preferable to Dynamic Ram ? > >In an ideal world, yes. Problem is, static takes up more room than dynamic >and it's much more expensive. You're much better off with a meg or two of >DRAM than 256K-512K of SRAM. > There's probably some confusion about different memory uses in the larger article Erick writes that Dave has not addressed here. Static RAM is rarely used as the main memory. It is most commonly used in external caches. Static RAM: fast, does not require a memory controller Dynamic RAM: denser (fewer chips for same memory size), more power efficient, less expensive Because of the cost, density, and power requirements of SRAM, it is used only in performance sensitive applications where its high speed is an absolute requirement and where total memory size is relatively modest. Examples include the memory of Digital Signal Processors and the cache memories of high performance general purpose computers. Because of the favourable cost/bit ratio DRAM is generally used for larger memory arrays. The cost and complexity of a DRAM memory controller becomes less significant compared to the total memory cost. Scott.