Forum Home
Press F1
Thread ID: 15605	2002-02-11 07:57:00	ram sorts	Guest (0)	Press F1

Post ID	Timestamp	Content	User
35333	2002-02-11 07:57:00	could somebody please explain the different types of ram to me	Guest (0)
35334	2002-02-11 08:22:00	very briefly...... edo....must be installed in pairs. only used on old machines and some printers/raid cards. sdram.....most comman at present. speeds range from 33-133mhz. 133mhz unbuffered sdram is the most comman you will find in shops. also advailable as registed ram and ECC, not normally used in home pc's. DDR....double data rate sdram. advailable in 200, 266, and 333mhz. mainly athlon systems but now some p4. at present good performance for $$$ in 1ghz+ systems. rdram.....p4 only (except some p3 systems) must be installed in pairs and empty sockets have to have blanks installed. has larger bandwidth than DDR but is expencive. generaly poor bang for $$$. i won't even dare go into the old 1 meg modules. i'll leave that to the oldies ;-)	Guest (0)
35335	2002-02-12 02:59:00	Core: ferrite toroids with hand threaded wires for drive and sensing. Very expensive. (Still used in eg Space Shuttle flight control computers, possibly still in aircraft crash recorders) NMOS 2102 1k x 1 static; 2114 1k x 4 static (18 pin DIP) Price for a populated 4k byte board using 2114 was about $250 as a kit around 1980. ... Seriously: 30 'pin' SIMM you probably won't see. Came in 256k, 1M, 4M, and one byte wide, so needed to be installed 4 at a time for 386DX and above. Each 1M about $120 in 1991. Speeds 50nS - 120nS. 72 'pin' SIMM came in various sizes: 1M (rare), 4M, 8M, 16M, (and 32M -- very expensive). 4 bytes wide so needed to be installed in pairs for Pentium. Some 486 boards allowed (required?) pairs, so the banks could be interleaved for speed (accessed alternately). The type before EDO (extended data output) was FP (fast page access). Speed 50nS -- 80 nS mostly. The other types tweak'e mention have *lots* of pins. (SIMMs are referred to as having 'pins' because previously there were SIPPs which were the same, except they had pins instead of edge connector positions ).	Guest (0)
1