Rdram Rambus Memory Rambus RDRAM 184-Pin 232-Pin PC-800  PC-1066  PC-1200
 

RDRAM RAMBUS MEMORY
www.rdramrambusmemory.com

| What is RAM and what does it do? | Different types of RAM | How to identify the size of RAM modules? | How to install RAM? | Frequently asked questions on computer memory RAM | Computer Memory Upgrade Websites | Mixing different kinds of RAM brands | What is DDR SDRAM and Rambus RAM ? | Which DDR RAM to buy? |

Looking to buy RAMBUS memory? Click here.

Can you mix memory brands?

Mixing brands can often cause problems

Using cheap no-brand, generic RAM can also be a common a source of system failure, so make sure that you purchase RAM manufactured by one of the major manufacturers such as Crucial, PNY, Kingston, Samsung, Panasonic, Corsair, etc.

Cheap, no-brand RAM can be especially prone to failure if the processor has been overclocked to a faster speed than its designated speed by increasing the system bus, from a default of, say, 100MHz to 112MHz, if the 112MHz setting is supported by the motherboard but probably not by the RAM. The cheap RAM will probably not be able to handle the increase and cause Fatal Exception and Page Fault failures.

The motherboard's newsgroup will also contain postings about troublesome brands, or anomalies, such as having 64MB of RAM working perfectly well and 128MB, as two by 64MB modules, refusing to work.

All of the PC's purchased during the last three years should be able to cache as much RAM as you are likely to install.

 

Also make sure that it is of the right type (EDO/SDRAM/, buffered/unbuffered, error-checking code (ECC) RAM, etc.), and check the motherboard's website for compatibility issues. The specifications will be listed in the motherboard's manual.

Windows 98 can itself use as much RAM as any current motherboard. However, installing more than 64MB of RAM on a system running the original (FAT 16) version of Windows 95 will slow the system down. Not being able to cache more than that amount of RAM means that it takes its time accessing it. Windows 95 versions OSR 2.0, 2.1, and 2.5 (FAT 32 versions) can all cache the same amount of RAM as Windows 98.


Intel Pentium 4 processors

The first Pentium 4 processors run on Socket 423 motherboards, most of which support only Rambus RAM. But the latest incarnation of P4s run on Socket 478 motherboards, some of which support DDR RAM

The more expensive RamBus RAM, the RIMM modules of which have be installed in pairs, require dedicated slots that will not accept SDRAM or DDR RAM DIMM modules.

SDRAM modules do not have to be installed in pairs; single modules will function.

Not only do you have to purchase a dedicated motherboard for a Pentium 4, you also have to purchase a dedicated case to house it. A special power supply unit with extra power lines is required, and the case has to have extra stand-off points to support the motherboard.

For Intel Pentium III and Celeron processors, and AMD Athlon and Duron processors a standard mini, midi, or full tower ATX case is required to house ATX or micro-ATX (M-ATX) motherboards.

Another good reason to buy AMD. You can use a standard ATX case to house the motherboards that support all of its processors.

Just to give you an idea of the current cost difference between the latest DDR SDRAM and Rambus RDRAM, at the end of July 2001, 256MB of Crucial DDR SDRAM will cost approximately 36, including tax, while the same amount of Rambus RDRAM from a mail order company cost 188, including tax.


Ordinary SDRAM comes in types that run at official speeds of 66, 100, and 133MHz, i.e., usually at the same speed as the default Front Sided Bus (FSB) speed of the motherboard.

The FSB is the network of interconnections between the various parts of the motherboard.

DDR SDRAM uses a new technique to transfer data that effectively doubles its speed. This kind of RAM is being used on motherboards that run AMD Socket A Athlon and Duron processors, which are physically identical apart form the amount of onboard Level 2 cache they contain, and the bus speed that they run on - 100MHz for the Duron, and 133MHz for the Athlon.

PC 100 DDR RAM has been named PC 1600 SDRAM because of its data bandwidth (transfer capacity) of 1.6GB per second. A Socket A motherboard must specifically support it. Motherboards with this capability are available from most of the major motherboard manufacturers.

In short, PC 1600 SDRAM is the DDR equivalent of ordinary PC100 SDRAM.

But further confusion is being added with the advent of PC 2100 DDR RAM, which is just the DDR version of PC 133 SDRAM. It was named PC 2100 because it has a data bandwidth of 2.1GB per second. Special Socket A motherboards support it and the new range of Athlon XP processors that use it. These motherboards will have a 133MHz FSB and a 266MHz bus speed between the processor and the RAM memory.

Earlier Athlon processors (Thunderbirds) that use 100MHz FSB are marked with a B, and the new ones using the 133MHz FSB are marked with a C.

The Duron range of processors will keep running on a 100MHz FSB with a 200MHz processor-to-RAM bus speed.

Just remember that you need to buy a motherboard with a chipset that supports PC 2100 DDR SDRAM if you want to run the Thunderbird Athlons that use it, or one of the new Athlon XP processors.

The VIA KT133A is such a chipset. It supports both B and C suffixed AMD Thunderbird processors.

As you will note in the information on Crucial's RAM pricing, provided further down this article, PC2700 and PC3200 DDR RAM (also known as DDR333 and DDR400 respectively) is now available. - See the table below for a list of DDR RAM.


Still confused about the different types of RAM?

It is very easy to become confused with the different types of RAM that will or will not run on the different types of motherboards that support Intel or AMD processors.

Start by remembering that motherboards that support Intel processors never support AMD processors, and you are half way towards clearing up the confusion.

The motherboard must support a given processor if you are to use it. It is then just an simple matter of consulting the motherboard's manual to find out the types of RAM and the processors that it supports.

You can download the manuals from the websites of most of the major motherboard manufacturers. As long as you only install items on a motherboard certified by its manual to run on or with it, you cannot go very far wrong.

Most systems that have motherboards that use SIMM memory modules require you to use matching pairs of modules to fill a bank of slots on your motherboard. If you fail to match them correctly, your system will probably not function properly.

For example, if you want to install 64MB of EDO RAM that comes in the outdated SIMM module form, you may have to install two matching 32MB modules instead of going with just one 64MB module, or one 32MB module plus two 16MB modules. Therefore, always check your system and motherboard manuals before you place an order.

Note that you do not need to install DIMM (SDRAM or DDR RAM) modules,in pairs. Modern motherboards are also often much more forgiving about which DIMM modules that can be fitted - they do not all have to be of the same capacity. - A 64MB module can be installed with 128MB and 256MB modules.

Remember, never skimp on quality when it comes to RAM.

Even when buying a new PC always obtain a system specification and check what make of RAM is installed.

Only grade-A memory will do, and it is only manufactured by the major manufacturers of RAM.

RAM is probably the most critical system component. Every bit of data passes through it to get to the processor, so it has to be 100% functional 100% of the time if data corruption is not to take place.

It is a fact that many program crashes can be attributed to cheap, error-prone or defective RAM. Therefore, if the system has generic, low-cost RAM, insist that grade A RAM from one of the major manufacturers is installed.

The major manufacturers of RAM are Crucial Technology (also known as Micron Technology), Rambus (http://www.rambus.com/) PNY (uses Siemens chips), Kingston, Corsair, LG, Hyundai, Mushkin, and Samsung.

If the vendor's advertisement, or system specification does not name the manufacturer, then it is usually generic RAM that is on offer, much of which is not likely to be grade A RAM.


Which DDR RAM?

The problem

You want to purchase an ECS K76SA motherboard, and 256MB of PC2100 or PC2700 DDR RAM. You want to run an AMD Duron 1.3GHz processor on the motherboard's front-side bus (FSB) that runs at 200MHz with this processor installed. You know that both PC2100 and PC2700 DDR RAM run faster than 200MHz, so you want to know if the RAM you purchase will be able to run at the slower bus speed used by the processor.

Answer

Even though the processor has a maximum speed (frequency) of 1.3GHz (1300MHz), the effective data transfer rate of the processor is limited to the speed (frequency) of the motherboard's FSB, which in this case, doubled by DDR technology, is only 200MHz. The FSB speed is the speed with which the processor is able to communicate with the rest of the system. It can do its own calculations at 1.3GHz, but, in this case, can only communicate with the rest of the system at 200MHz. This is going to limit the effective speed of the DDR RAM, because the RAM can but won't tranfer data faster than the processor.

The chipsets on AMD Athlon/Duron motherboards allow the RAM bus to run at a different speed from the processor bus.

For example, the base FSB on the above ECS motherboard running a Duron processor is 100MHz, because that is the FSB used by that processor. The processor is able to operate at the DDR (double-data rate), which is 200MHz. (Later Athlon processors use a 133MHz FSB.) If PC133 SDRAM, which runs at 133MHz, is used, the Duron processor has an effective data transfer rate that is 67MHz faster than the RAM, so in this case the slower RAM is creating the bottleneck that is limiting the data transfer speed. But with DDR RAM installed, the processor's effective data transfer speed would be responsible for creating the bottleneck.

Below is a table providing information on the different types of DDR RAM.

Names

Base FSB Speed DDR RAM Speed
PC-1600 or DDR-200 100MHz 200 MHz
PC-2100 or DDR-266 133MHz 266 MHz
PC-2400 or DDR-300 150MHz 300 MHz
PC-2700 or DDR-333 166MHz 333 MHz
PC-3200 or DDR-400 200MHz 400 MHz

If you purchase PC2700 RAM, the Duron 1.3GHz processor runs on a base FSB of 100MHz, doubled to give an effective data transfer speed of 200MHz, while the RAM runs on a base FSB of 166MHz, which is effectively 333MHz using the DDR technology. So, in this case, the processor is creating the bottleneck by having an effective data transfer rate that is 133MHz slower than the RAM.

The motherboard's manual provides the information on the types of RAM that the motherboard can run. You must set the RAM clock speed (in the BIOS, or by setting jumpers on the motherboard) to the speed of the RAM that your purchase. This is 133MHz for PC2100 and 166MHz for PC2700 DDR RAM.

Therefore, if you wanted the RAM speed to match the processor speed, you would install PC1600 DDR RAM. However, you could purchase the highest type of DDR RAM supported by the motherboard. If you decided to upgrade the processor to the highest AMD Athlon processor that it supports, that processor will run on a base FSB of 133MHz, providing an effective data transfer speed of 266MHz. The ECS motherboard supports PC2700 DDR RAM, so if that is installed with the new processor, the effective data transfer rate would be increased from 200MHz to 266MHz, and the bottleneck between the RAM and processor would be reduced from 133Mhz to 66MHz.

The latest AMD XP processors run on a base FSB of 166MHz (DDR 333MHz), so they will transfer data across the system bus at the same speed as PC2700 (DDR 333) RAM. But PC3200 (DDR 400) RAM runs at 400MHz, so the base motherboard FSB would have to run at 200MHz for one of these processors to transfer data across the system bus at the same speed as PC3200 RAM.


Some memory questions

Does it matter which slots I plug my new module in?

In general, you will get the best performance if you put the largest module (in megabytes) in the lowest-numbered slot. For example, if your computer comes with 32MB of removable memory and you want to add 128MB, it would be best to put the 128MB module into slot 0 and the 32MB module into slot 1.

Why Does the Price of Memory Fluctuate?

Supply and demand. Occasional changes in market demands will alter inventories and, therefore, raise or lower prices.

Can you mix and match ECC and non-parity modules?

No. When adding new memory, you need to match what is already in your system. You can determine if your system has parity by simply counting the number of black memory chips on each module. Parity and ECC memory modules have a chip count divisible by three or five. Any chip count not divisible by three or five indicates a non-parity memory module.

Can DDR and SDRAM be used in the same system at the same time?

No. Even though there are systems that support both technologies, you can't have DDR and SDRAM in the same system at the same time. You'll have to choose one or the other.

"Have you ever gotten a "great deal" on a system and then been a little disappointed with its overall performance? If so, this article on Crucial's Web site is for you. Get the information you need to figure out whether or not upgrading your system would be worth the money.

What are MultiMediaCards?

About the size of a postage stamp, a MultiMediaCard, or MMC, is a small, removable storage device used in a variety of electronic devices, including digital cameras, handheld computers, and digital music players. MultiMediaCards are designed with flash technology, a non-volatile storage solution that does not lose its information once power is removed from the card. MultiMediaCards contain no moving parts and are extremely rugged, providing users with much greater protection of their data than conventional magnetic disk drives.

More memory questions answered, click here!


RAM diagnostic utilities

Memtest-86 3.0

http://www.memtest86.com./

MemTest v1.2 [9k] W9x/2k/XP - free - http://www.mywebattack.com/gnomeapp.php?id=105570 and

http://www.simmtester.com/page/products/doc/download.asp


RAM websites

The "Ultimate Memory Guide." - http://www.kingston.com/tools/umg/default.asp

If you want to know about the technical details of how RAM works, visit this article. -

How Computer Memory Works - http://www.howstuffworks.com/computer-memory.htm.

And if you want to know how Windows, and other operating systems, make use of a virtual memory swap file on a hard disk drive to expand the system's RAM, read the following article. -

How Virtual Memory Works -

http://www.howstuffworks.com/virtual-memory.htm

"Windows 98 & WinME Memory Management" - http://aumha.org/articles.htm - includes information on RAM and the Windows Virtual Memory swap file.


RAM News

RAM Wars: Return of the JEDEC

JEDEC = Joint Electronic Device Engineering Council

"DDRAM comes into its own right for mainstream and performance PC applications while muscling out SDRAM and Rambus. Here's our analysis of the world of PC memory as it is being shaped by DDR. We also take a look at GDRII and GDRIII."

"This year will bring a radical change in the kind of memory you will buy and how you will buy it. The death knell has begun to sound for SDRAM while DDRAM has become a standard memory device. A bevy of new memory capabilities, such as dual channel DDR, will make life that much more interesting."

http://www.tomshardware.com/mainboard/20030401/index.html

Rambus RAM exceeds 1GHz

Rambus RAM is now available running at a frequency exceeding 1GHz. The new 1006MHz (1.006GHz) Rambus RAM, combined with Intel's 850E chipset and the latest Pentium 4b processor, takes full advantage of the latest 533MHz motherboard front side bus (FSB) frequency. Asus is the first motheboard manufacturer to issue a motherboard - the P4T533 - that supports the new memory.

Micron (Crucial) demo the next generation of memory technology

http://www.simmtester.com/page/news/shownews.asp?num=4597

Reported Memory Does Not Match Installed Memory

RAM information from Microsoft

"When you view the Performance tab in System properties, the amount of memory reported may differ from the actual amount of memory installed in the computer. This behavior can occur for any of the following reasons: Himem.sys is not using all the memory on an EISA computer. A driver or program loading from the Config.sys or Autoexec.bat file is claiming a portion of random access memory (RAM). A virtual device driver loading from the System.ini file is claiming a portion of RAM. A protected-mode driver is causing the memory mismatch. The registry is damaged. A CMOS setting is disabling some of the RAM. You have the 'maxphyspage=' setting in your System.ini file set to restrict Windows from using some of the installed memory. Ramdrive.sys is being loaded in the Config.sys file. You are using a video adapter that is integrated into the motherboard." -

http://support.microsoft.com/default.aspx?scid=kb;EN-US;Q146912



16-bit Rambus RDRAM memory (184 pins)
This type of RAM is increasing in popularity. These modules operate at up to 533Mhz speed compared to 133Mhz for SDRAM. Most Pentium 4 systems support RDRAM modules for top performance.
PC800 Rambus RIMM (RDRAM) - 184 pins
64Mb Rambus RIMM Samsung
184pins, PC800, 40ns, 16-bit, MR16R1622DF0-CM8
Manufacturer: Samsung, Warranty: Lifetime.

128Mb Rambus RIMM Samsung
184pins, PC800, 40ns, 16-bit, MR16R1624AF0-CM8
Manufacturer: Samsung, Warranty: Lifetime.

256Mb Rambus RIMM Samsung
184pins, PC800, 40ns, 16-bit, MR16R1628DF0-CM8
Manufacturer: Samsung, Warranty: Lifetime.

512Mb Rambus RIMM Samsung
184pins, PC800, 40ns, 16-bit, MR16R162GDF0-CM8
Manufacturer: Samsung, Warranty: Lifetime.

128Mb ECC Rambus RIMM Samsung
184pins, PC800, 40ns, 18-bit, ECC Error Correction
MR18R1624AF0-CM8, Manufacturer: Samsung
Warranty: Lifetime.

256Mb ECC Rambus RIMM Elpida Stock clearance!
184pins, PC800, 40ns, 18-bit, ECC Error Correction
MC-4R256FKE8D-840, Manufacturer: Elpida
Warranty: 2 years.

256Mb ECC Rambus RIMM Samsung
184pins, PC800, 40ns, 18-bit, ECC Error Correction
MR18R1628DF0-CM8, Manufacturer: Samsung
Warranty: Lifetime.

512Mb ECC Rambus RIMM Samsung
184pins, PC800, 40ns, 18-bit, ECC Error Correction
MR18R162GAF0-CM8, Manufacturer: Samsung
Warranty: Lifetime.
PC1066 Rambus RIMM (RDRAM) - 184 pins - for overclocking

Special offer on Samsung PC1066 RDRAM 184 pins
128Mb, 256Mb, 512Mb

128Mb Rambus PC1066 RDRAM (RIMM2100)
184 pins, 16-bit, 1066Mhz, RIMM2100, 32ns, for Intel
850E chipsets, P/N: MR16R1624DF0-CT9,
Manufacturer: Samsung, Warranty: 10 years.

256Mb Rambus PC1066 RDRAM (RIMM2100)
184 pins, 16-bit, 1066Mhz, RIMM2100, 32ns, for Intel
850E chipsets, P/N: MR16R1628DF0-CT9.
Manufacturer: Samsung, Warranty: 10 years.

256Mb Rambus PC1066 RDRAM (RIMM2100)
184 pins, 16-bit, 1066Mhz, RIMM2100, 32ns
for Intel 850E, P/N: KVR1066X16-8/256,
Manufacturer: Kingston, Warranty: Lifetime.

512Mb Rambus PC1066 RDRAM (RIMM2100)
184 pins, 16-bit, 1066Mhz, RIMM2100, 32ns, for Intel
850E chipsets, P/N: MR16R162GDF0-CT9,
Manufacturer: Samsung, Warranty: 10 years
PC1200 Rambus RIMM (RDRAM) - 184 pins - for overclocking

256Mb Rambus PC1200 RDRAM (RIMM2400) - OCZ New product!
184 pins, 16-bit, 1200Mhz, RIMM2400, 32ns
Suitable for i850E and SIS658 chipsets, non-ECC
Bandwidth 4,8Gb/s Dual Channel,Manufacturer: OCZ Technology, Warranty: Lifetime.

Upgrade Kits (special deals on 2 modules)

128Mb RIMM Upgrade Kit, Samsung
(2x 64Mb modules), 184pins, PC800, 40ns, non-ECC
Manufacturer: Samsung, Warranty: Lifetime.


256Mb RIMM Upgrade Kit, Samsung
(2x 128Mb modules), 184pins, PC800, 40ns, non-ECC
Manufacturer: Samsung, Warranty: Lifetime.

512Mb RIMM Upgrade Kit, Samsung
(2x 256Mb modules), 184pins, PC800, 40ns, non-ECC
Manufacturer: Samsung, Warranty: Lifetime.

1Gb RIMM Upgrade Kit, Samsung
(2x 512Mb modules), 184pins, PC800, 40ns, non-ECC
Manufacturer: Samsung, Warranty: Lifetime.

256Mb ECC RIMM Upgrade Kit, Samsung
(2x 128Mb modules), 184pins, PC800, 40ns, 18 bit, ECC
Manufacturer: Samsung, Warranty: Lifetime.

512Mb ECC RIMM Upgrade Kit, Samsung
(2x 256Mb modules), 184pins, PC800, 40ns, 18 bit, ECC
Manufacturer: Samsung, Warranty: Lifetime.

1Gb ECC RIMM Upgrade Kit, Samsung
(2x 512Mb modules), 184pins, PC800, 40ns, 18 bit, ECC
Manufacturer: Samsung, Warranty: Lifetime .
32-bit Rambus RDRAM memory (232 pins)
32-bit Rambus modules provides two independent memory channels, which means there is no requirement to install these modules in pairs of two.
RIMM3200 modules provide a memory bandwidth of 3,2Gb/s, RIMM4200 provides 4,2Gb/s and RIMM4800 provides an unparalleled transfer rate of 4,8Gb/s.
PC800 Rambus RIMM3200 - 232 pins
256Mb Rambus RIMM PC800 32 bit (RIMM3200)
232 pins, 32-bit, PC800, RIMM3200, 40ns MD16R1628AF0-CM8, non-ECC.
Manufacturer: Samsung, Warranty: Lifetime
PC1066 Rambus RIMM4200 - 232 pins - for overclocking

256Mb Rambus PC1066 32-bit RDRAM (RIMM4200)
232 pins, 32 bit, 1066Mhz, RIMM4200, 32ns
for Intel 850 chipsets, P/N: MD16R1628AF0-CN9
Non-ECC, Manufacturer: Samsung, Warranty: 10 years


512Mb Rambus PC1066 32-bit RDRAM (RIMM4200)
232 pins, 32 bit, 1066Mhz, RIMM4200, 32ns
for Intel 850 chipsets, P/N: MD16R162GDF0-CT9
Non-ECC, Manufacturer: Samsung, Warranty: 10 years

512Mb ECC Rambus PC1066 32-bit RDRAM (RIMM4200)
232 pins, 32 bit, 1066Mhz, RIMM4200, 32ns
for Intel 850 chipsets, P/N: MD18R162GAF0-CN9
ECC Error Correction, Manufacturer: Samsung, Warranty: 10 years
PC1200 Rambus RIMM4800 - 232 pins - for overclocking

256Mb Rambus RIMM PC1200 32 bit (RIMM4800) - OCZ
232 pins, 32-bit, PC1200, RIMM4800, 32ns
4.8 Gb/s transfer, non-ECC, Manufacturer: OCZ, Warranty: Lifetime

 

| What is RAM and what does it do? | Different types of RAM | How to identify the size of RAM modules? | How to install RAM? | Frequently asked questions on computer memory RAM | Computer Memory Upgrade Websites | Mixing different kinds of RAM brands | What is DDR SDRAM and Rambus RAM ? | Which DDR RAM to buy? |

RAMBUS RDRAM PC800 PC1066 Memory RAM Upgrades


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Offers Rdram rambus memory types PC800, PC1066, PC1200 16-bit, 32-bit non-ECC and ECC, Rambus RIMM Upgrade kits. RDRAM RAMBUS Memory. PC1066 533Mhz, PC800 40ns RAMBUS Memory, RAMBUS PC800 45ns 400Mhz, RAMBUS PC600 Memory Upgrades.

   
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  256MB PC800 40NS RAMBUS Memory

 

  256MB Kit PC800 40NS RAMBUS Memory

 

  512MB Kit PC800 40ns RAMBUS Memory

 

  Samsung 512MB Kit 40ns PC800 rambus Memory

 

  Samsung 512MB Kit PC800 40ns ECC Memory

 

  1Gb Kit 533MHZ RAMBUS Memory

 

  1Gb Kit 533Mhz ECC RAMBUS Memory

    
 

  PC800 45ns RAMBUS Memory

 

  64MB RDRAM RAMBUS 800mhz 45ns Memory

 

  128MB RDRAM RAMBUS 800mhz 45ns Memory

 

  256MB RDRAM RAMBUS PC800 45ns Memory

 

  256MB ECC RDRAM RAMBUS PC800 45ns Memory

 

  512MB RDRAM RAMBUS 800mhz 45ns Memory

 

  512MB ECC RDRAM RAMBUS 800mhz 45ns Memory

 

  1Gb kit (2 x 512MB) 1024mb RDRAM RAMBUS 800mhz 45ns Memory

 

  1Gb kit (2 x 512MB) 1024mb ECC RDRAM RAMBUS 800mhz 45ns Memory

    
 

  PC600 RAMBUS Memory

 

  128MB PC600 ECC RAMBUS Memory

 

  256MB PC600 RAMBUS Memory

 

  256MB PC600 ECC RAMBUS Memory

 

  512MB PC600 RAMBUS Memory

 

  512MB PC600 ECC RAMBUS Memory