In order to qualify as PC100, PC133, etc., a memory module must meet industry standards for use in a particular type of system. In SDRAM modules, the numbers that come after the "PC" refer to the speed of the system's front side bus. In DDR modules, the numbers that come after the "PC" refer to the total bandwidth of the module. Here's a short summary of each type. PC100 memory is SDRAM designed for use in systems with a 100MHz front side bus.

A PC100 or PC133 compliant memory includes a label affixed to it which identifies the module as "PC100 compliant" or "PC133 compliant" . An attempt can be made to verify it by looking at the chip marking which should indicate "-8" or "-7.5" after the string of manufacturer part number, though this may not be entirely accurate.

PC1600 is designed for use in systems with a 100MHz front-side bus (effectively 200MHz in DDR mode). PC2100 is designed for use in systems with a 133MHz front-side bus (effectively 266MHz). However, since PC2100 was designed to be backward compatible, it has essentially replaced PC1600 in systems with a 100MHz front-side bus.

Yes. However, if you have a system with both PC1600 and PC2100 modules, the system will only run at a speed of PC1600. A system will only run at PC2100 if all the modules in it are PC2100 and the system supports PC2100.

Yes. The AC timing specifications on a PC133 device are tested to allow a system bus to run at 133 MHz. Majority of PC133 chips should work at PC100 and PC66. In fact, a -75 device is specified for PC100 timings using CAS latency = 2. Please refer manufacturer data sheet for AC timing table in the appropriate data sheet tCK at CL = 2.

PC2100 DDR is designed for use in systems and motherboards which require a 133MHz front-side bus. While the system or motherboard may operate a 133MHz front-side bus, its effective front-side bus speed is 266MHz in DDR operation. To get the effective front-side bus speed of a DDR system, double the operating frequency. PC2700 DDR is designed for use in systems and motherboards which require a 166MHz front-side bus, with an effective front-side bus speed of 333MHz.

a general rule, SDRAM is backwards compatible, therefore a PC133 Dimm can operate at 133Mhz, 100Mhz and 66Mhz. Certain systems though that require 66Mhz SDRAM modules will not accept PC100 or PC133 modules. In addition to the speed, the chip configuration of the module is also important. Use our memory search facility located on our home page at (http://www.offtek.co.uk) for guaranteed compatibility.

If your PC has a 100MHz FSB, you can use PC100 or PC133 SDRAM. All PC’s that accept PC100 SDRAM will also accept PC133 SDRAM; however, your memory will only run as fast as the slowest link in your system. If you have a 100MHz FSB or any PC100 modules installed, any PC133 modules that you install will only operate at 100MHz. PC133 SDRAM does not offer any immediate benefit over PC100 SDRAM if you have a 100MHz FSB.

If your PC has a 100MHz FSB, you can use PC100 or PC133 SDRAM. All PCs that accept PC100 SDRAM will also accept PC133 SDRAM; however, your memory will only run as fast as the slowest "link" in your system. If you have a 100MHz FSB or any PC100 modules installed, any PC133 modules that you install will only operate at 100MHz. PC133 SDRAM doesn't offer any immediate benefit over PC100 SDRAM if you have a 100MHz FSB.

DDR memory has been manufactured to be backward compatible so you can add faster memory modules to your machine. For example, if you install a PC2700 module alongside an original PC2100 module the memory will work and be fully compatible but you will not gain any performance benefit, as the PC2700 module will be clocking down to PC2100 to run alongside the original PC2100 module installed. Dual channel refers to the DDR/DDR2 chipset on specific motherboards that have two memory channels.

Yes. Usually it is recommended to use the same ram modules for all ram slots, but it should work without problems if you mix different brands, speed grades, sizes. If you use a FSB of 100Mhz, you can't use PC66 dimms, and if you overclock your FSB to 133Mhz, you need PC133 modules (you can of course try to use modules not rated for that speed, but you shouldn't be surprised if it doesn't work stable).

Usually it is fine to mix PC100 and PC133 memory in the same system. The faster memory will run at the slower memory's speed (in this case PC100). However, there are some rare instances in which this memory configuration will not work. Contact your computer manufacturer or motherboard manual for more information.

Generally all SDRAM is backward compatible and can run at any bus speed slower than it is rated to run. For example, a PC133 SDRAM DIMM is capable of running at 133MHz, 100MHz, and 66MHz. There are a few older motherboards that require 66MHz SDRAM and that will not accept PC100 or PC133 SDRAM, but they are the exceptions to the rule.

This is the Bus speed between the CPU (Central Processing Unit) and your memory on the FSB (Front Side Bus). PC66 transfers data at 66MHz, PC100 transfers data at 100MHz and PC133 transfers data at 133MHz.

Although these are all types of double data rate (DDR) memory, the varying numbers refer to the different speeds of memory your computer was designed for. Crucial no longer carries PC2100 (DDR266) memory, but PC2700 (DDR333) memory and PC3200 (DDR400) are backward-compatible with PC2100. Memory is designed to be backward-compatible, so generally speaking, you can safely add faster memory to a computer that was designed to run slower memory.

d" stands for "development". "b" stands for "beta test". For example, version 3.0b12 is "the 12th beta test version of MT-NewsWatcher 3.0". In general, all development versions precede all beta versions. So, for example, version 3.0d17 is earlier than 3.0b15. Version 3.0 final has no letter, and is just plain "3.0". All of the development and beta versions are earlier (older) than version 3.0 final.

Yes, only if you have a 100 MHz system bus. No,if you have a 66 MHz system bus. On certain system, a non-PC100 module may be "pushed" to run in a 100 MHz system, but the results are not guaranteed and may lead to system instability. Majority of Pentium Pro P6 Computers uses 72 Pin SIMMs. Installation requires 2 SIMMs per bank to upgrade memory. (2 sockets per bank)

The number 720 or 1080 refers to the number of vertical lines that make up each picture frame, while the letter describes how those lines are displayed. The ‘p’ stands for progressive, meaning that all the lines are shown in one go. 1080i means half the lines are shown, followed by the other half every 50th of a second. As to which type is best ~ that depends on the type of programme you are watching.

D2 is the type of petrodiesel that's used in the summertime. In the winter it's mixed with D1 to improve cold weather performance. Biodiesel can be used straight, as B100 (100% biodiesel) or in any blend with any kind of petrodiesel. B20 (20% biodiesel) is a popular blend, along with B2, B5, B50, and B99. People often use the terms B99 and B100 interchangeably. There can be, just as with D2. This is a factor that all biodiesel users should be aware of.