What is... the motherboard?

To install a hard disk

What is... the memory RAM?

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What is... the BIOS?


Basic configuration

Has it already copied the current configuration of his BIOS in a few sheets of paper? And to what waiting? Anyway... under the name of Standard CMOS Setup or similar, it usually include the putting on the day of the date and hour of the system, as well as the configuration of hard disks and disk drives. The handling screen is usually similar to this one:

Pantallazo of the BIOS showing the parameters of the hard disk

To change the date and hour does not have any more history than to place on her and to introduce the piece of news, good by means of the keyboard, the mouse, the cursors or the keys of advance and regression of page. Practise a little with it, this way it will be prepared for when it is going to change something more critical.

The type of disk drive and screen is also simple to understand and to handle. Except prehistoric cases the screen will be VGA or EGA, and the above mentioned it is already quite strange; when he says "monochrome" it usually refers to screens MGA, those of white, green phosphorus or amber of more than ten years ago, not to the VGA of scale of gray modern, bear it in mind.

The most interesting and difficult thing is in the configuration of the hard disks. In general they will be only neither discs of the type IDE (including the EIDE, Ata-4, Ultra-DMA and other enlargement of the standard), in no case SCSI (go, almost a couplet, SCSI says to himself "it is - ca-si") nor ancient others like MFM or ESDI, which are formed of other forms, for example by means of another BIOS of the proper checker SCSI.

In the ancient cases (many 486 and previous) we will be able to give values only to two hard disks, which the first one and Slave form like Teacher, master's degree, slave, the second one, of the only channel available IDE. In the most modern cases of checkers EIDE we will be able to form up to four, in two channels IDE, each one with his teacher and his slave. For those who do not understand anything of this, I recommend the reading of the paragraph to Install a hard disk.

The fields to be refilled are usually:

  • Type (Type): or the predefined one, or Edict so that the computer calculates the correct values, or User to introduce the values to hand, or None to indicate that there is no disc.
  • Size (Size): the computer calculates it from the information that we introduce.
  • Cylinders (Cylinders): since that, how many are.
  • Heads (Heads): the above mentioned, how many are.
  • Precompensation of writing (WritePrecomp): a very technical parameter used especially on the ancient discs. In the modern ones it is usually a zero.
  • Area of parked of the heads (LandZone): another technicism, which nowadays is usually zero or 65535 (that in fact means zero).
  • Sectors (Sectors): since that, how many are there for every track.
  • Way of functioning (Mode): for small discs, of less than 528 MB, the Normal way. For discs of more than 528 MB (modern anyone has 4 ó 5 times this capacity), the way LBA or the Large, less secondhand and only recommended if the LBA was not working. In many cases there is allowed the autodetection (option Edict).

For example, in the image a 420 MB disc appears, with 986 cylinders, 16 heads... and being employed at Normal way, since it does not overcome 528 MB. All these values usually come in a sticker adhered to the hard disk, or can be by means of the utility of autodetection of hard disks, which learns further on.

In any case, generally there exists more than one possible combination of values. Certainly, the readership of CD - ROM of type IDE is not formed usually in the BIOS; this way, although really they occupy one of the places (the teacher of the second channel or the slave of the first one) usually owes to allow the above mentioned pigeonholes in target, electing None or Edict as a type.


Options of the BIOS

Or generally, in English, BIOS Features. It is a question of the diverse possibilities that the BIOS offers to realize certain tasks of one or another form, in addition to enabling (enable) or disabling (disable) some characteristics. The most important are:

  • CPU Internal catches: the paymaster or disabled of the internal cache memory of the microprocessor. It must be enabled (to set in Enabled) for any chip with internal cache memory (all from 486). If we disable it, we can do that our Pentium 75 goes like 386 rapidly, which does not serve for anything as it is not to play a very ancient game that goes too rapidly in our computer.
  • External Caché: the same but with the external cache memory or of the second level. It does not have so many transcendency like the intern, but enough influences the yield.
  • Quick Power On Self Test: that the cross-check test, on having started, becomes more rapid. If we are sure that everything works well, it is worth doing it to gain a few seconds on having started.
  • Boot Sequence: so that the computer looks first for the operating system on a diskette and then on the hard disk if it is "To, C" or the other way round if it is "C, A". Useful to start or not from diskettes, or in modern BIOS even from a unit Zip or internal SuperDisk.
  • Swap Floppy Drive: if we have two disk drives (To and B), the order exchanges them temporarily.
  • Boot Up NumLock Status: for those who prefer to start with the numerical keyboard formed like cursors instead of how numbers.
  • IDE HDD Block Mode: a type of transference "for blocks" of the information of the hard disk. 100 MB almost all the hard disks from now on support it.
Pantallazo showing the screen "BIOS Features Setup" of a classic BIOS
  • Gate A20 Option: a technicism of the RAM; better connected.
  • Above 1 MB Memory Test: if we want that it verifies only the first MB of RAM or quite (above = "over"). The first thing is more rapid but less sure, obviously, although if it has never failed: why should it do it now?
  • Memory Parity Check: it verifies the bit of parity of the memory RAM. It must only be used if the RAM is with parity, what at present is very rare, so much in FPM as EDO or SDRAM. The only memoirs with parity are usually in 486s or mark Pentium, as some IBM.
  • Typematic Rate: to fix the number of characters in second that appear when we touch a key during a few moments without releasing it. Only useful for maniacs; one day it is said that it is for disabled, but I am afraid that his utility in this sense is unfortunately very scarce.
  • Numeric Processor: to indicate the computer that a mathematical co-processor exists. Since from the appearance of 486 DX this happens of course, it is in extinction process.
  • Security Option: although sometimes it comes in another menu, this option allows to choose if we want to use a password or password whenever we start the team (System), only to modify the BIOS (Setup or BIOS) or never (Disabled).
  • IDE Second Channel Option: it indicates if we are going to use or not the second channel IDE (only in checkers EIDE, skylight), in whose case reserves an IRQ, generally 15.
  • PCI/VGA Palette Snoop: this is too complex and risky him to dare to tie up, although if he wants an answer I will say to him that it usually use when we have two videocards (or an added card sintonizadora of television) and the colors do not appear correctly. Be sent to the manual of his graphic card to see if he must enable it.
  • Video Bios ROM Shadow: if it is enabled, it will copy the