We are going to exhibit the fundamental concepts about one of the less attractive operations of maintenance for the user, for his high risk... and nevertheless one of the most common and most important, especially given the vertiginous current rhythm of renewal of the hardware.
Generalities: what is the BIOS and types
Before starting with the mechanics of the matter, we must think a little what the BIOS is, and how it turns out to be possible to update it.
The BIOS is a computer program (that is to say, it is a software) that is stored in a chip of the motherboard, generally of rectangular form and approximately 4 x 1,5 cm, with 28 small legs. This "cockroach" is the standard format, although in some cases other chips are used or there is integrated to a chip multifunctionality (like FirmWare Hub of the badges with chipset Intel 820).
The program of the BIOS has an important characteristic that separates it from the normal programs: it must not resign on having extinguished the computer. For it, it is stored in a chip of memory of the type ROM (Read Only Memory, memory of only reading) instead of in the habitual memory RAM.
Nevertheless, the ROM used in the chips of BIOS is not completely inalterable, but it is of the type EEPROM (Electrically Erasable and Programmable Read-Only Memory, memory "of only reading" removable and programmable electrically), what allows to update it.
There exist two types of chips of BIOS:
- the EEPROM in strict sense;
- the EEPROM Flash ROM.
In the modern basic badges (more or less from the appearance of the Pentium) the Flash ROM is used, because they have the big advantage of which they can be updated by the user by means of a simple program software, while the EEPROM (more ancient) need to be withdrawn and introduced in a special device to be rewritings.
Most of the following exhibition will refer to the update of BIOS of the type Flash, although in the end we will treat little aspects hardware of the update of BIOS EEPROM.
Before starting...
1. - The first thing of everything is to assure us of that we need to update the BIOS. Many people update the BIOS to try to solve problems that not at all have to do with her, but with the operating system or the drivers, for example; and position that it is a question of something lightly risked, it is convenient to be sure that it is necessary.
We already saw what class of things we will be able to solve: lacking in support in some microprocessor, incompatibilities with some concrete hardware, problems of starter... and also some questions of instability of the team (the "hangs" of the system), but bear in mind that most of the awesome blue screens of Windows has not anything in common with the BIOS. Just in case, check everything and verify that it has installed the last drivers (of video, of the chipset...).
2. - The following and fundamental thing is to identify completely the motherboard:
- Manufacturer (ASUS, Iwill, ABIT, AOpen, QDI, Soyo, Fic...)
- Model
(generally a combination of numbers and letters type "BX6", "CC820"...) - Version (in some cases it will be an important knowledge if the version or review is 1.0, the 1.1, her 2.0b...)
For it, the best thing is to consult the manual of the motherboard, or straight to open the team (bearing in mind that this might annul his guarantee and taking the precautions described in Essentials of the Update) and to look in the badge for a serigrafiado and/or tags (often given to the grooves PCI or ISA) with this information.
If it does not find any indication, he can observe the first screen that appears on having started the team (that one in which the memory of the system appears, the hard disks are detected and sets a little like "Press XXX to enter Setup"). There should appear the name of the manufacturer of the BIOS (Award, AMI, Phoenix...) and that of the motherboard, or at least a long chain of numbers and numbers of the style of the following one:

Aim at it in a role (it turns out to be something difficult for the rapid thing that disappears, but perhaps be able to stop the starter process touching the key "Pause") and consult this web page, in "Award Numbers" o "AMI Numbers" depending on the manufacturer of the BIOS.
If the BIOS is of the mark Award, also it can be fixed in the last group of numbers; the characters 6 and 7 identify the manufacturer, according to the following list (5 previous ones generally refer to the chipset). If it is AMI, be fixed in the third group of numbers and consult the available list on this web page.
3.-Now only he can only enter his current BIOS (as he explains himself on the page: What is... the BIOS?) and to aim at all the values that appear in the same one. This will facilitate to him very much the process of configuration of new BIOS, especially if it does not know thoroughly what the parameters of the BIOS mean.
4. - Ah, an additional precaution: some BIOS has a protection to prevent his erasure for virus; consult the manual of the motherboard or look a little like "BIOS-ROM Flash Protect" and form it like "Flashable" or "Disabled".