Basic Input Output System (BIOS) is a set of basic programs for testing the computer equipment during its running, booting of operating system and also to support exchange of data between devices. Basic Input Output System is stored on ROM (read-only memory). The programs of BIOS define a general productivity of a computer and in most cases are not inaccessible for users.
Actually, BIOS is a small microchip with a set of micro commands that control the operation of all devices on a motherboard. When you switch your computer, a processor sends a signal to BIOS that initiates the loading of low-level micro program “BOOT-ROUTINE”. At first, a subprogram POST (Power-On Self Test) boots; it checks the capability of the processor, operating memory and also assistive devices. Then BOOT-ROUTINE searches and initialized the other BIOS that can be installed on other motherboards. For example, almost all modern video cards have their own BIOS.
Then BIOS allocates the system resources between found devices. They are assigned with numbers of IRQ, channels of direct access to DMA, addresses of input/output ports and other. Finally, there will be a boot table where you can find the main accessible devices and allocated resources.
Then BIOS launches a micro program “BOOTSTRAP LOADER” which is the bootstrap loader. This program scans the devices that may contain media with boot record. This leads to downloading of an appropriate operating system.
This is the most common sequence of BIOS operation but there are a lot of supplements and changes, connected with operation of each particular BIOS.
DDR SDRAM is a future step in the development of a usual SDRAM. A technology Double Data Rate (DDR) enables to use the front and back fronts of clock pulse for information exchange. This increases twice the amount of transmitted information. Thus, an effective frequency of memory bus exceeds twice a frequency of operating bus.
General recommendations for choosing DDR SDRAM is similar to those for SDRAM as there is no fundamental difference between SDRAM and DDR SDRAM.
Nowadays the following modules of memory can be used: PC1600 – 100 MHz, PC2100 – 266 MHz and PC2700 – 333 MHz.
The CL latency time for such modules may have the values 3, 2.5 and 2.
The computer’s capacity directly depends on three elements: processor, chipset and operating memory. If the processor and chipset are rather expensive and almost unchangeable components of the system, an operating memory could be changed.
Remember that you can get a high-speed and reliable system using a qualitative memory. Before buying it, discover the bus frequency of your computer and the time of delays of desired module.
Nowadays SDRAM often occurs in the form of DIMM (Dual In-Line Memory Module). This memory can be found in middle-class computers.
The least losses when sending data will be observed during synchronous exchange of information between the processor and memory. So when selecting a memory module, pay attention not only to the amount of stored data, but also to a frequency: PC100 – 100 MHz, PC133 – 133 MHz, PC166 – 166 MHz.
Another important parameter of SDRAM is the time delay, connected with searching data in the memory (CAS Latency). This value defines the time needed to search the column with data. This amount is identified by CL on a module and has a value equal to 2 or 3 clocks. CL can be installed using BIOS but, as a rule, if there is a marking “CL=3” on a module, the decreasing of this value leads to an unstable operation of a computer. That’s why, it is better to buy modules with a marking “CL=2” for higher speed of computers.
There are two types of processors for desktop systems – Intel and AMD. You can also find the processors by Cyrix, Rise, Centaur, VIA, SIS, Transmeta, Compaq and other but nowadays these companies cannot compete Intel and AMD.
Processor is a main object for overclocking, so its selection determines if you could increase the working capacity of your computer or not. The selection of processor, in turn, affects the selection of motherboard. If you insert the processor by Intel in the motherboard by Intel, you get good steadily-operating system but almost unoverclockable. You can get some result only from outdated systems with the processors Pentium II or Pentium III. That’s why the manufacturers of a motherboard and chipset must be different, for example, by VIA or SIS, and a motherboard by Abit, Albatron or EPoX.
As a rule, a manufacturer of processors produces a line of similar processors that differ only by the value of multiplying ratio of a system bus. The price of such line is allocated as follows: the lower ratio, the cheaper processor. For example, if it is possible to change the multiplying ratio of a bus at the hardware or software level, the low-cost or cheap processor can be overclocked to the frequency of more expensive processors. But in most cases (especially in modern processors) the multiplying ratio is strictly fixed at the hardware level and cannot be changed. Thus, there is one possibility to overclock your computer – to increase the frequency of FSB. This allows getting the increase of frequency from 10% to 30-35%.
If you buy a processor with the possibility to overclock it in future, keep a close watch on prices on the other models of the same line. The best way is to but a low-cost processor with good fan that has a powerful radiator.
In addition to basic devices, a motherboard also must combine a lot of peripherals. Of course, the quality of connected equipment would depend greatly on the quality and quantity of available ports, connectors and slots.
At the present stage of computer development, the change speed of standards is rather high. For example, a standard of AGP bus frequency, that is equal to 66 MHz, is now ousted by SuperAGP bus with a frequency of 100 MHz, and a protocol of data exchange from ATA has increased from 33 to 133 Mbt/s and has eliminated IDE-loops.
In most cases, it is better not to save on a motherboard and buy it “with the reserve” in order you could easy update all peripherals in future. While selecting a motherboard, draw attention to the following moments:
- The higher number of connectors for memory modules, the better is result as the memory has a significant impact on your computer’s performance;
- For full functionality, especially at home, your motherboard must have one AGP-connector, compatible with 4X standard or higher;
- An amount of connectors for PCI-devices must be not higher than four;
- If you use outdated ISA-devices, make sure that you have all appropriate connectors;
- Your USB-port has to be compatible with 2.0 standard and have at least two connectors.
An integrated video is a decent way to save your money and to get video image of average quality. This is quite enough for office tasks or non-resource-intensive games. It is necessary to buy a separate video card for complex tasks, connected with the processing of video images, and resource-intensive games.
Integrated video cards use operating memory as video memory and central processor as video processor, consuming a significant part of system resources. A size of allocated memory may be static or dynamic. In the former case, a fixed value of allocated memory is set from 0,5 to 128 MB through BIOS. 4-8 MB is sufficient for many tasks, but you may need a larger amount of memory for games. Remember, that allocated memory becomes unavailable for the rest system almost disappears. So, for example, if you allocate 16 MB out of 32 MB of operating memory to video card, you work at the computer will be very difficult. From the other side, if you allocate only 0,5 MB of memory, a viewing of video will be like a slide-show.
If you allocate the memory dynamically, an operating system allocated a necessary amount of memory depending on the tasks to be performed. For example, only 4 MB of memory will be allocated when working in Word, 32 MB – when playing in Quake and 4 MB – if you return to Word.
In general, integrated video cards are only suitable for low-cost office computers in spite of their decent opportunities. For home usage, buy better video card. If no such possibility exists, provide an additional operating memory. Do not combine the use of built-in and peripheral video cards, as the first one consumes system resources, regardless of the type of video system you use.
Nowadays a lot of motherboards include audio and video. As a result, they are more expensive but there is no need to buy sound or video cards.
It is rather difficult to select between integrated sound and video expansion cards. First of all, the use of a simple audio codec of AC 97 Standard leads to a significant worsening of a sound palette even in comparison with the outdated sound cards for ISA-bus. Besides, audio processing is handled by a processor. So, the purchase of a motherboard with built-in dual-channel (2.0 Index) codec AC 97 is warranted only by its budget construction. But if you have separate sound, you must switch off you built-in s audio codec. To switch it off, select the value “Disable” for the parameter “AC 97 Audio” in a section “Integrated Peripherals” in BIOS Settings.
From the other side, a lot of manufacturers produce their motherboards with built-in codec or even sound processors of good quality. For example, a codec Analog Device which is used in chipsets by Intel, or DSP (Digital Signal Processor) which is used in chipsets by nVidea. Thus, one motherboard has got five- or six-channel sound card (4.1 or 5.1 Indexes accordingly). Of course, if you have such motherboard, there is no need to use a separate expansion card.
If you use cheap simple speakers, the choice between a built-in codec and sound card makes almost no difference in the sound quality. The better sound, the better your speakers should be and the higher requirements should be applied to audio codec and sound card.
Soltek Company produces cheap motherboards for overclocking.
A motherboard by this company has got a set of technologies providing overclocking. In fact, it is only enough to switch your computer on and it will select all necessary parameters for overclocking itself. For example, if you use “RedStorm Overclcokng”, there will be a function that automatically increases the bus frequency with the step of 1 MHz and checks the system sustainability. If your system is sustainable, the frequency will be increased, otherwise the parameter is given a previous frequency value and your computer restarts.
Motherboards by Soltek have a lot of tools for overclocking. Not to damage equipment, there are also various control systems both on the hardware and the software levels. Here you can establish temperature ceilings, define the speeds of the blowers, select the way of automatic caution and other.
Motherboards by Soltek are ideal for cheap computers and not very experienced users.
The product by MSI is one of the most popular and wide-spread as it is very qualitative and its prices range a lot. Accordingly, it has a variation of possibilities for overclocking: from extremely low and limited to the best ones.
The main features of these motherboards are their performance reliability and multifunctionality. A Motherboard by MSI consists of a CD with a lot of utilities that enable to protect your computer from unauthorized entry, to get information about the system and equipment, to update BIOS automatically (LiveUpdate Utility), to monitor a system, to control an exact temperature, voltages and operation of fans and to start overclcoking directly from operating environment of Windows (Core Center Utility).
MSI Company has pioneered D-Bracket Technology that enables to control the system loading using LEDs, placed on a special panel at the back of the system unit. There are also additional USB-connectors on this panel.
Motherboards by Intel are best selling ones. A motherboard by Intel is completed with a chipset by Intel, BIOS microcircuit by Intel and with a processor by Intel. Such structure, combined with a big amount of brand technologies, provides an optimal performance of equipment. But there are also several important limitations. First of all, the products by Intel are not cheap. The functional possibilities of motherboards and supported technologies are directly depend on their prices – the cheaper products have locked opportunities at the hardware level and, in most cases, there is no “manual” unlocking. When the unlocking is possible, there is a high risk to damage both a motherboard and a processor. Secondly, it is impossible to overclock anything in a motherboard by Intel: in most cases the possibility to change a bus frequency and the processor multiplying ratio is locked. But there are the parameters associated with configuring the bus frequencies, PCI and AGP.
Most motherboards are equipped with BIOS by Intel but some models may have Award BIOS. One of their features is the possibility to recover BIOS from the backup file. You can do this using a switch on a motherboard which can be set in Normal, Config or BIOS Recovery.