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Thread ID: 26465	2002-10-28 05:21:00	SIMM & DIMM	fergie (424)	Press F1

Post ID	Timestamp	Content	User
93757	2002-10-28 05:21:00	Hi, Could someone tell me the difference between SIMM and DIMM RAM? What do they stand for? Do both work have the same M/B requirements? What is the difference - faster, slower, bigger etc	fergie (424)
93758	2002-10-28 05:30:00	This (www.pcengines.com) is the simm buyer's guide, it has some good deatils on it. and here (www.tyan.com) is a glossary telling u about simm, dimm and othe pc stuff. DIMM (Dual In-line Memory Modules) are a faster and more capacious form of RAM than SIMMs, and do not need to be installed in pairs. SIMM (Single In-line Memory Modules) are the most common form of RAM. They must be installed in pairs, and do not have the carrying capacity or the speed of DIMMs.	vk_dre (195)
93759	2002-10-28 05:30:00	SIMM stands for Single Inline Memory Module. DIMM stands for Double Inline Memory Module.	Elephant (599)
93760	2002-10-28 05:33:00	thanks for that. another thing - do DIMM have chips on both sides of the board? and SIMM only 1 side?	fergie (424)
93761	2002-10-28 05:40:00	> another thing - do DIMM have chips on both sides of > the board? and SIMM only 1 side? yes, dimm have chips on both sides of the board and simm only has 1 side with chips. that's why simms are to be installed in pairs and dimm in singles. cheers, v.K	vk_dre (195)
93762	2002-10-28 07:28:00	> > another thing - do DIMM have chips on both sides > of > > the board? and SIMM only 1 side? > > yes, dimm have chips on both sides of the board and > simm only has 1 side with chips. that's why simms are > to be installed in pairs and dimm in singles. Ummm... No :D Some SIMMs have chips on both sides, and some DIMMs have chips on only one side. Usually a DIMM is 168 pin, and SIMMs were the older 70 pin ones (although that's not entirely accurate). Mike.	Mike (15)
93763	2002-10-28 07:30:00	>>> and SIMMs were the older 70 pin ones Woops, that should rather be 30 pin and 72 pin ones :p Mike.	Mike (15)
93764	2002-10-28 07:32:00	oh yeah, wot ever, :D just kiddin, i stand corrected.	vk_dre (195)
93765	2002-10-28 08:23:00	Well first of all SIMMs (single inline memory module), DIMMs (dual inline memory module) and RIMMs (I have no idea) are all DRAM (dyanamic random access memory) packages. There are earlier packages like SIPPs and DIPPs but if you want to know about those too I'd be glad to tell you about those or point you to sites that would explain them. SIMMs came in two sizes 30pin (8 bits wide) and 72pin (32 bits wide), you installed them dependant on your CPU's external data bus in special SIMM sockets (30 pins usually four to fill a bank and 72pins usually pairs to fill a bank). The access speeds ranged from as slow as 200 nanoseconds on ancient 8088s, up to 50 nanoseconds for the last of the FPM (fast page mode) DRAM. DIMMs come in a wide variety of pin sizes, but the 168-pin DIMM currently dominates in modern systems. It's 64bits wide which means you would only need one to create a bank in a Pentium class or later motherboard. DIMMs handle new types of RAM such as SDRAM (synchronous), DDR (double data rate) SDRAM and RDRAM (Rambus). I didn't quite elaborate on the difference. The pin on one side of a SIMM does the same function as the pin on the opposite side. The function of a pin on one side of a DIMM is different as the pin on the opposite side. Also the speeds of DIMM are faster. If you have more questions or have to question what I say I'd be glad to try and explain and if I'm incorrect, I'd excpet that too.	~qwerty (2369)
93766	2002-10-28 18:44:00	thanks for tht. I have 2 PC's - ones about 3 years old, and the otehr is a year old. They both had 128mb RAM installed, i purchased 256mb (chips on 1 side only) SD-RAM. I put that into the newer PC, and took out the 128mb (which had chips on 1 side only) which i put into the older PC. So the older PC was going to have 2 sticks of 128mb. when i opend up the older PC, i saw that the ram in there currently had chips on both sides of the board - i didn't think that it would matter that i was putting in one with chips on teh one side. Any way, i booted up, and the computer reset as soon as it got into windows, it booted up in safe mode, and froze, i reset - no luck. I toook out the newer RAM (chips on 1 side) and the PC works fine. In the manauls for both Motherboards it says it supports 2 168 pin DIMM . What type of RAM does the older PC need?	fergie (424)
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