Different computer documentation

Everything that it is useful to know about BIOS

Unlike the car, maintenance of the PC does not demand knowledge of the mechanic, all interaction of computer gears happens at programming layer - by means of basic system of input/conclusion, i.e. BIOS. This material contains recommendations and the clarification, concerning various adjustments BIOS, understood in which, you can independently, without resorting to the help of the technology professional, to adjust the home PC.

We will not consider all options accessible in BIOS, we will be restricted only to what essential impact on stability or productivity of the computer can make or to expand PC functional capabilities. Regulation of other parameters is better to give to the system, i.e. to leave the values exposed by default.

In connection with a considerable quantity of vendors hardware and the software there is a set of varieties BIOS different from each other by the interface and a title of functions, therefore we not begin to be anchored to specific modifications BIOS, and for adjustments we result their most probable titles. We also will be restricted to reviewing only modern BIOS which are available in the computer of a typical configuration for today: the processor of class Pentium II, storage - PC100 SDRAM, a hard disk in volume from 2 GB, PCI or AGP a videocard, port USB presence. In certain cases our manual is useful and for older systems.

Before we pass to practice, it would be desirable to notify about necessity of observance of the elementary safety measures. So, changing parameters in BIOS, write down all actions - if there will be a problem with computer operation, you without effort recover initiating setting. Anyway always it is possible to return to the initial parameters set by the vendor for what it is necessary to use functions Load BIOS Defaults and Load Setup Defaults. The first exposes the most safe values of parameters BIOS that will be useful at recovery of serviceability of the computer, the second - optimal for normal system operation.

Considering all these remarks, we pass to most BIOS. At machine loading on the screen within several seconds the invitation, for example Hit DEL to enter Setup is displayed. Pushing at this time DEL key, you cause the menu with which help access is provided to adjustments BIOS. On title page it becomes Already clear that support of operation of the PC at a basic level is not unique mission BIOS. Here it is possible to find many simply useful options, for example access control support to the computer. In the main menu options Supervisor Password and User Password are for this purpose provided. With their help it is possible to set passwords on system loading, and only Supervisor Password allows to change adjustments in BIOS. Without knowledge of one of these passwords nobody gets access to the information stored on a hard disk or on any other carrier, installed in the computer. With unique method to crack system there will be an opening of the case and closing of special contacts on the motherboard (see its documentation). By the way, the same should be made, if you forget the password. Basically, it is possible to prevent and case opening: to seal up it or to put the lock on special crampons if those on the case are available.

One more possibility to restrict access to the information contained PC is switching-on of mode Read Only in menu Floppy Disk Access Control. It forbids record of files on diskettes so the outside person to copy the information without your permission it will not be possible. Besides, in this case it is required to install the password on access to adjustments BIOS.

Automatic switching-on and computer loading in preset time, and also its passage in a doze mode can become other useful options; in case of inactivity. It is necessary to mark that adjustment of power saving up modes for the monitor, a hard disk and system as a whole can be carried out and means Windows. In BIOS for this purpose it is necessary to include function Power Management. If in the case the power unit of standard ATX is installed, in menu Automatic Power Up it is possible to set exact time of start of the computer - ???????????, every day or in certain days of month. To get remote access to the computer and thus not to hold it permanently included (in a dream mode), it is possible to use mode PWR Up on Modem Act which allows BIOS to turn on the computer in reply to entering phone call. Thus for loading and a logging in passwords, and, besides, system should not be required initiates modem operation only after the loading so, connection procedure should be repeated. By the way, in such mode click of the tumbler of the modem can initialize computer switching-on. There are also other methods of start of the computer - pushing a gap or the mouse button (if they are connected through port PS/2) for what in BIOS there is option PWR up on PS2 KB/Mouse.

Continuing a subject of loading of the computer, we consider methods of acceleration of this process by means of adjustments BIOS. Probably, each time when you include the PC, you should watch process of testing of storage long. To reduce time which is required for carrying out of similar test procedures, it is necessary to activate option Quick Power On Self Test (or POST). To disconnect this option it is required only by search of a cause of defect of the PC as for its determination more careful testing at loading is necessary.

The modern motherboards allow to use almost any carrier installed in the PC for loading of the computer. In menu Boot Sequence it is possible to set sequence of reversal BIOS to system disks, combinations A, a C are thus possible; a C only; CD-ROM, a C; LS/ZIP, a C and others. It is recommended to select a variant in which the first interrogated device is the hard disk that the system did not waste time on inquiry of other drives from a normal situation. With the same purpose it is necessary to disconnect search of floppi-diskette Boot Up Floppy Seek that besides allows to get rid of enough unpleasant sound signal accompanying given procedure.

If in the future all the same there will be a necessity to boot from a diskette everything that it is necessary to make, it at computer start to enter in BIOS Setup and to change this option on A, a C (before insertion BIOS such choice is mandatory). In case in the computer are installed both IDE, and SCSI hard disks, there can be a need of switching-on HDD Sequence SCSI/IDE First. The matter is that by default to an IDE-disk value of a C and loading is appropriated produced from it. At changeover of this option on SCSI the user has an opportunity to allocate various operating systems on IDE and SCSI disks or simply to use SCSI a disk as the load.

Option Halt On is responsible for a stop of the computer in the course of initial self-test (POST) at failure detection or absence of the necessary device, for example keypads. Here it is possible to set to the condition computer at which loading will be continued: All Errors - at any errors, All But Disk/Key - at everything, except keypad and disk errors, and etc.

Computer loading can be paused also at Boot-virus detection. Are responsible for given function Virus Warning and Boot Virus Detection. These modes work differently: Virus Warning forbids any record in load sector of a hard disk that as ghost effect, by the way, prevents also setting of operating system Windows 9x. Boot Virus Detection in the course of loading displays notifying message in case contents of load sector differ from beforehand saved in storage. Further, at the discretion of the user, it is possible either to continue loading, or to reboot the PC, using the system floppy.

Section IDE HDD Auto detection gives possibility of automatic determination of parameters of a hard disk and a mode choice in which that will work. Normally it is offered to the user two or three variants from which in case of the modern disks in volume more than 528 MB optimal is mode LBA. Received after procedure of automatic determination parameters should be set evidently, including mode USER Type HDD that accelerates computer loading for some seconds which will be spent each time otherwise for automatic determination of the same parameters. Mode AUTO, on the other hand, is useful to that does not demand change of adjustments BIOS in case of disk changeover.

Mode Floppy 3 Mode is the Japanese standard for the floppi-disk drive and is not used in other countries so in menu Floppy 3 Mode Support this point should be ignored.

Mode UDMA is supported by all modern hard disks and allows to raise system performance as a whole. Its switch-off can be necessary only in case of front-side bus operation on supernumerary frequencies about what it will be told more low more in detail.

HDD S.M.A.R.T. capability the technology of self-diagnostics and disk condition monitoring "is decrypted and translated as". With its help it is possible to prevent in advance information loss at hard disk failure. The system traces normal operation of mechanical and electronic elements of the drive and estimates its state by comparing of current parameters with the put threshold values. Activation of this function reduces productivity of the computer a little, but guarantees safety of the data that is especially actual for removable disk drives.

Function IDE HDD Block Mode Sectors (in other modifications BIOS can be called Multi-Sector Transfers) allows to tell some sectors for one clock period that, naturally, raises high-speed performance. Mode Maximum installs an amount of sectors in the unit equal to the maximum value that, however, not always is an optimal mode for the drive. For setting of the best value it is necessary to address to the hard disk documentation.

Some versions BIOS give formatting possibility, however we at all would not recommend to play about without extreme need with this option.

Understood with optimization of loading of the computer and hard disk operation, we pass to more granular controls. The modern motherboards allow to install frequency, pressure of a supply and other parameters of the processor not by means of jumpers on the board, and through BIOS. For change of frequency of the front-side bus it is necessary to select Manual from menu CPU Speed. For stable operation of the processor on supernumerary frequencies, probably, magnification CPU Vcore - pressure of a supply of a kernel is required. The user, however, should realize that setting of the given parameter over standard value can cause a processor output out of operation, and it is optional at once. It is connected to magnification of probability of migration of electrons, i.e. their driving on "unbeaten" tracks. In the beginning it leads to errors, and further - to unrecoverable damages of a microstructure of the processor.

Increase of frequency of the front-side bus, besides, can become the reason of hangup of system because of origin of problems with a hard disk, and also expansion cards - video, sound and other. Frequencies on which these components will work, are resulted in menu CPU Bus/PCI Freq. Values from above 37 MHz can lead to disk failures (especially if that works in mode UDMA) and, probably, to ????? all information on it. Proceeding from it, we recommend to use the offered values in menu CPU Speed, and also nominal frequency of the front-side bus and pressure CPU Vcore.

Let's consider other parameters regulating operation of the processor. BIOS Update (other variant of a title - Pentium II Microcode) - this mechanism is necessary for loading of the microcode containing bug fixings in processors of class Pentium II. Switching-on of the given option raises stability of system operation.

To disconnect parameter CPU L1 Cache and CPU L2 Cache it is not necessary, as it leads to the considerable decline of productivity and does not give any positive effect.

CPU L2 cache ECC checking: at switching-on of an option stability of system operation can raise at the expense of the error correcting mechanism in cache memories of the second level of the processor, however high-speed performance thus decreases.

To squeeze out of the system an additional gain of productivity, it is necessary to address to random access memory adjustments. SDRAM Configuration specifies, whether should BIOS install independently temporal parameters of a memory access on the basis of the information from unit SPD in the storage unit (by SPD) or to allow it to make to the user (Disabled). We urgently recommend not to include the last mode. The maximum high-speed performance of storage is reached at minimum values of values CAS Latency, RAS to CAS delay which can be set, selecting 7ns (143 MHz) from menu SDRAM Configuration.

Not all storage chips will steadily work at such adjustment, therefore at their purchase it is necessary to take an interest at the seller, besides correspondence of the unit of storage to standards PC100 or PC133, also in parameter CAS Latency which is normally designated CL=2 and CL=3. Storage with CL=2 has the maximum high-speed performance and stablly works on frequencies 100-133 MHz.

In case you use the type of storage ECC SDRAM containing the mechanism of error correcting, switching-on of option DRAM Data Integrity Mode can raise stability of system.

Now we pass to the adjustments regulating operation of a graphic subsystem. If in the computer are installed simultaneously both AGP, and PCI videocards, VGA BIOS Sequence allows to select, which will be involved first of all.

Parameter Graphics Aperture Size needs to be installed at a rate of the order of 50 % or 25 % from random access memory volume - optimal value should be specified in the videocard documentation. At acceleration of the front-side bus reduction of this value can solve a problem of unstable operation of the videocard.

Some non-standard videocards, such as separate 3D-accelerators or boards for MPEG-video playing, can incorrectly display colors. In this case it is necessary to include function PCI/VGA Palette Snoop.

By means of menu Video Memory Cache Mode the technology of caching of video memory Uncacheable, Speculative Write Combine (USWC) which accelerates an output of a drawing to the display is activated. If the card does not support the given function, it is necessary to change this parameter on UC.

Switching-on of mode Video ROM BIOS Shadow can accelerate operation of games under DOS, but does not affect in any way high-speed performance of Windows applications. The same concerns and other setting of type Shadow C8000 - CBFFF.

For normal operation of ISA-payments many setting are provided. In new computers such devices meet very rarely, moreover, on the modern motherboards ISA-SLOTS can miss generally. However in the PCs collected two and more years ago, network and sound cards are installed in the core in ISA-SLOTS. Their usage (especially it concerns sound cards) essentially reduces productivity in games and multimedia applications.

While there is a data interchange with the ISA-device, bus PCI actually stands idle. To reduce this time, it is necessary to include mode PCI Delayed Transaction. Similar action renders mechanism Passive Release which allows buses ISA and PCI to work parallely. Both PCI Delayed Transaction, and Passive Release will be involved only at activation of option PCI 2.1 Support.

For optimization of operation of boards ISA setting 8 and 16 bit I/O Recovery Time are used also. Value 0 or N/A normally gives a productivity gain if, of course, such parameters are comprehensible to a board. For normal functioning of some ISA-cards it is required to include option Memory Hole at 15M-16M.

As to adjustment of other devices of input/conclusion and expansion cards, it is possible to make following recommendations: if your system has port of the mouse of standard PS/2 and thus you use serial port for its connection, from menu PS/2 Mouse Function Control select Disabled. Otherwise leave AUTO. The Same concerns and devices USB: if you do not use them and BIOS gives such possibility, port USB is better for disconnecting.

Insertion BIOS.

Update BIOS can be useful both for performance gain and stability of system, and for correct recognition of processors, compatibility with new hard disks, videocards and other components.

On the official web site of the vendor of the motherboard it is possible to find special utilities in section Download for insertion BIOS and current versions BIOS for each specific motherboard. After loading it is necessary to unpack and save the utility for an insertion and a new image BIOS in a readily available directory, for example C:\ABC. Then write down on a paper the full titles of an executed file, for example aflash.exe, and the image, for example Bx2i1011.awd. After that produce restart of system by means of the loading manager (for its call it is necessary to retain key F8 during start). From the menu select Safe Mode Command Prompt Only. When there will be a command line, pass in directory ABC by means of a command cd ABC and launch the utility, typing aflash.exe.

The insertion program normally allows to save prior version BIOS that it is recommended to make. For record of the new version the utility can request a title and a site of a new image BIOS, in our case it will be ?:\ABC\Bx2i1011.awd. On termination of procedure of update and an output from the program it is necessary to ungear the computer and then, after switching-on, to enter in BIOS SETUP and to activate function LOAD Setup Defaults, at an output from SETUP it is necessary to save changes. Now procedure of update BIOS is completed.

Extremely important at update BIOS to be guided by following rules. At first, to produce procedure in as much as possible stable conditions, especially it concerns power supply - it is desirable to use a source of an uninterrupted supply. If the system is dispersed, it is necessary to return it in a regular mode.

When in the course of update BIOS there are malfunctions, in no event it is impossible to ungear the computer. Try to repeat process or to register the old image saved in the beginning. If also it does not help, it is required to address to experts to replace the chip in which contains BIOS.

For secure in case of an unsuccessful insertion it is recommended to save also the utility and an image a load disk. Last is better to create, rebooting system in mode DOS (Start/Shut Down/Restart in MS DOS Mode) and typing in a command line C:\Format A:/S. It is not necessary to copy on this disk files Autoexec.bat and Config.sys. If the system can boot with such diskettes, try to repeat procedure anew.

At update BIOS it is necessary to consider that you assume overall responsibility for possible failure of your system. If the motherboard and the installed devices work stablly, and new versions BIOS do not contain substantial improvements, we do not recommend to produce this operation - among other things, reinsertion BIOS can cause necessity of reinstallation of an operating system.

There are the utilities, allowing to change parameters BIOS directly from an operating system. The greatest popularity uses Tweak BIOS. The program is intended for optimization of operation of a chipset of the motherboard, the central processor and the videocard and gives access to regulations which frequently are not shown in BIOS motherboards. That fact is remarkable that the utility is capable to change parameters on the fly, without demanding reboot and without updating a microcode in ROM BIOS. It is compatible practically to all existing chipsets and graphics accelerators and does not depend on version BIOS installed in the computer.

The parameters set by means of free variant TweakBIOS, will be effective till the moment of reboot or computer switch-off. The registered version allows to save these adjustments in a file and to load each time at PC start.

Appearance of the program reminds standard interface BIOS from Award Software. Relocation under the menu is accompanied by the useful helps how change of this or that parameter affects productivity. It is important to mark that "game" with these adjustments can lead to computer hangup so usage of the utility demands from the user of appropriate level of knowledge and skills. Anyway developers notify that they do not carry responsibility for ????? information or the failed hardware components in connection with usage TweakBIOS.