In this paper I will be discussing the differences and similarities between DDR2 SDRAM, DDR SDRAM, SDRAM, and RAMBUS RAM. The five main topics on RAM I will be discussing are architecture, speed, compatibility, comparison, and type, along with cost as a side factor.
First off is DDR2, which stands for Double-Data rate, which is, until recently, the most up to date DDR type. DDR2’s architecture, which is 240 pin, and have one notch near the center of the edge connector. DDR2 comes in a variety of different speeds measured in MHz, these speeds vary from 400 MHz, to 800 MHz. DDR2’s compatibility is used mostly with Intel compatible Motherboards, recently AMD released new AM2 socket compatible CPU’s which will support DDR2 type RAM. The model types for DDR2 are rated at PC2-3200 all the way to PC2-8500, some even higher than that! That name for the RAM also indicates it’s theoretical bandwidth. So when you are purchasing DDR2 RAM, it is important to look at two speeds, the MHz, and the PC2 rating. Out of the four types of RAM I have listed, DDR2 is the fastest, it is also not the most expensive. Both RAMBUS RAM, and DDR RAM, are still more expensive. RAMBUS RAM is more costly because you need to have both slots filled, and you also need to register it wit the company. I don’t know for sure DDR is more expensive, but in my opinion it is because of the AMD users. At tigerdirect.com, and online computer super store, they are constantly having DDR2 sales, and hardly ever DDR sales. For me this is a big problem, since I use a 939-socket Motherboard, which only supports DDR RAM. So in the long run, and with current prices and technology, DDR2 is the smart way to go. It will save you money in purchasing, along with its power saving features DDR lacks. Sure, DDR3 just got released, but with the current prices of the RAM along with a new compatible Motherboard, DDR2 is the smart, safe option.
DDR is older RAM technology, but is still widely used in AMD compatible machines like socket-939 for example. The architecture is a little different from DDR2. This RAM has 184 pin’s, with it’s notch more offset to the right. Also the speed, and throughput are slower. The speeds of DDR RAM vary, but are slower that it’s older brother, DDR2. The speeds of DDR vary from DDR-200, which is 200Mhz, to a top speed of 400 MHz. This is where DDR2 picks up where DDR left off going 400Mhz and above. As I said, DDR price’s are just starting to go down, (ha, right after I bought my 1 gig of DDR RAM..) I feel this is due to two factors. First is AMD switching to AM2 socket, which only supports DDR2. Another factor is the release of DDR3, which is adding competition in speed for gamers, against DDR2. This pretty much puts DDR out of the picture since there are two better options above it now. DDR Modules are like PC-1600, PC-2100, and PC-2700 and so on. They are the theoretical bandwidth of that RAM, so that PC number is what you need to look at when purchasing RAM. The higher the number, the faster that RAM will be, just make sure you motherboard supports that. You can always use higher frequency RAM, just not lower.
How much RAM do you need??? (Article from Maximum PC)
So, after reading this article in Maximum PC, they have informed me that 1-2GB is the new standard in most machines today. Also that that is quickly becoming to little for today’s OS systems like Vista which kills RAM. I have Vista Home Premium, with 1.2Gb of DDR333 RAM, and I am just able to do pretty much everything I need. But for you intense games out there or graphical artist, 2GB of RAM is a must for Vista users.
SDRAM is an older version of RAM. It stands for synchronous DRAM or single data rate. Since DDR and DDR2 stand for double data rate, it makes this obsolete. This RAM’s architecture is different that DDR and DDR 2. SDRAM has two notches, it also uses 168 pins, or 144-pin SO-RAM. SDRAM is synced with the system clock and is rated by clock speed. Some speeds for SDRAM are PC100, which is 100MHz.
RAMBUS RAM is developed by Rambus, Inc. this was though to overtake, or compete with DIMMS, but that dident happen. See, when you buy Rambus RAM you need to buy two sticks of it, or buy what is called a C-RIMM, which is like a RAM stick, but it doesent have any memory. Another factor to Ramus RAM no succeeding it that it needs to be registered, this costs money, so why should you spend more when you can get the same quality for a cheaper price? Rambus ram had 184-pin’s, and has two notches in the center. The C-RIMM is the same, it even has the gold teeth on it! At
http://www.kingston.com I read about Rambus RAM. Kingston has decided to take it off the market, there will still be warranties on them, and some warranties to buy as well. A cool fact about Rambus RAM is that Nintendo 64, as well as the Playstation gaming consoles use Rambus RAM. In 1999 Rambus RAM offered higher speeds than the current technology. Pc800 offered 800Mhz with 1600 MB/sec Bandwidth, which was significantly faster than the current PC133 SDRAM, but there where some downsides too. RDRAM put out a lot of heat, this required a heatsink to the RAM, also the latency of this RAM was to high as well, not to mention the cost.
