What is BIOS?
BIOS or Basic Input/Output System is the first program accessed by the processor during start up to ensure that all the other basic programs, hard drives, ports, peripherals and the central processing unit are in good working condition. BIOS is different from the computer's operating system. The operating system resides in the hard drive and provides the user interface that can be seen on the screen after start up. The BIOS program, on the other hand, can be found right in a flash memory chip or ROM located in the motherboard. It is the basic requirement for booting a computer.
DDR/DDR1/DDR3
DDR SDRAM, or Double Data Rate Synchronous DRAM, is a memory technology that doubles data throughput to the processor. This type of memory dramatically improves the memory system's ability to service high multimedia requirements, such as 3-D graphics .Power consumption: 2.5 V instead of 3.3 V.Memory bus runs at the same frequency as the CPU front side bus ..... 184 pin connection
DDR 2 - 240 pins , power consumption: 1.8 V instead of 2.5 V.
| Feature DDR2 DDR1 |
| Data transfer rate 400,533,667,800 1066Mhz 200,266,333,400 Mhz |
| Densities 256mb - 4 gb 64mb - 1 gb |
DDR and DDR2 both fall under the category of synchronous dynamic random access memory (SDRAM). The main area where DDR2 and DDR differ is in the speed of the bus. A DDR2 bus is twice the speed of a DDR bus. DDR2 can thus transfer more memory cells per cycle. This means that DDR2 can transfer four memory cells' worth of data in half the time of DDR.
DDR2 is faster because the interface used in its construction is more electrically sound. Due to these electrical improvements the latency (read time) is increased substantially. DDR typically has a latency of about two to three bus cycles per time the memory is read while DDR2 has a latency of between four and six cycles. This is compensated for in DDR2 due to the aforementioned increase in bus speed when using DDR2. Latency when dealing with RAM is measured in nanoseconds.
DDR3 SDRAM (Double Data Rate Three Synchronous Dynamic Random Access Memory) is the third generation of DDR SDRAM.DDR3 SDRAM improves on DDR2 SDRAM in several significant ways:
* Higher bandwidth due to increased clock rate
* Reduced power consumption due to 90mm fabrication technology
* Pre-fetch buffer is doubled to 8 bits to further increase performance
The voltage of DDR3 SDRAM DIMM's was lowered from 1.8V to 1.5V. This reduces power consumption and heat generation, as well as enabling more dense memory configurations for higher capacities.
DDR3 SDRAM improves on DDR2 SDRAM in several significant ways:
* Higher bandwidth due to increased clock rate
* Reduced power consumption due to 90mm fabrication technology
* Pre-fetch buffer is doubled to 8 bits to further increase performance
The voltage of DDR3 SDRAM DIMM's was lowered from 1.8V to 1.5V. This reduces power consumption and heat generation, as well as enabling more dense memory configurations for higher capacities.
In a single channel memory system the memory modules are installed on one channel, with only one route to access the memory controller (which manages the data communication between the installed memory and the rest of the system).
In dual channel memory systems, the memory modules are installed on two separate channels, each with its own route to access the memory controller, thus doubling the peak data bandwidth.
In triple channel memory systems, the memory modules are installed on three separate channels, each with its own access to the memory controller, thus tripling the theoretical peak bandwidth when compared to single channel mode. Please note that the new Intel Core i7 processor has the memory controller integrated into it. The benefit is that the front side bus (FSB) and its related latency have now disappeared.
ACPI
Short for Advanced Configuration and Power Interface, a power management specification developed by Intel, Microsoft, and Toshiba. ACPI, which will be part of the next version of Windows, enables the operating system to control the amount of power given to each device attached to the computer. With ACPI, the operating system can turn off peripheral devices, such as a CD-ROM players, when they're not in use. As another example, ACPI will enable manufacturers to produce computers that automatically power up as soon as you touch the keyboard.
Virtual Memory
Virtual memory is the space allocated on hard drive for memory management functions. With virtual memory, what the computer can do is look at RAM for areas that have not been used recently and copy them onto the hard disk. This frees up space in RAM to load the new application.
EIST
Enhanced Intel SpeedStep Technology (EIST) is a power reduction feature; processors that include EIST consume less processing power. If the software applications in use do not require the maximum processor power, the processor runs in a lower power state.
