What is a BIOS?
BIOS is an acronym meaning Basic Input / Output System. It is stored in a chip called ROM (read only memory). Most of the latest motherboards now use EEPROM's (Electrically Erasable Programmable Read-Only Memory)
(also called "Flash" BIOS) which can usually be upgraded by the user. (The
earlier versions of the BIOS had to have the chip physically removed and replaced with a
another chip programmed with a later BIOS version.) When you switch on your computer the
BIOS is the first program to run . It initializes and tests the hardware in your computer
(called Power On Self Test or POST). When everything is
running, the BIOS program initiates and loads the operating system. The information in the
BIOS can be changed by running Setup (sometimes called CMOS Setup). A set of routines
called Run-Time Services, which is also a function of the BIOS, help
operating systems and application programs to manage the hardware.
BIOS Flash Upgrades
Flashing your computer bios can be a very intimidating chore.
Many users are unfamiliar with this type of activity and are
apprehensive about doing things that could potentially damage or
render their system inoperable. Because of these risks, we advise
users to flash their bios only if the newer bios will fix a specific
problem that they are having. With computer bios upgrades, newer
is not always better.
|Flash ROM Voltage and Block Size|
|EEPROM chip ||Voltage ||Block Size ||BIOS binary file|
|MX28F1000PX ||12 V ||Large 16 K ||(xxxxxxx)L.bin|
|MX28F1000PL ||12 V ||Large 16 K ||(xxxxxxx)L.bin|
|MX28F1000PC ||12 V ||Large 16 K ||(xxxxxxx)L.bin|
|MX28F1000PPC ||12 V ||small 4 K ||(xxxxxxx)s.bin|
|i28F001BX-T120 ||12 V ||small 4 K ||(xxxxxxx)s.bin|
|SST 29EE010 ||5 V ||small 4 K ||(xxxxxxx)s.bin|
|Winbond 29EE011 ||5 V ||small 4 K ||(xxxxxxx)s.bin|
|ATMEL 29C010 ||5 V ||small 4 K ||(xxxxxxx)s.bin|
Who made my motherboard
In order to obtain an updated BIOS for your system, you will need
to identify the motherboard manufacturer and BIOS identification
number. To do this, reboot the machine. You will need to record the
BIOS ID string, which will be located at the bottom-left corner
during startup. On most systems, you can press the Pause key
during the memory test to suspend the process and allow more
time to properly copy the ID string.
CTBIOS ID Program
If you can boot your motherboard use
to reveal the possible manufacturer for motherboards older than 1997.
Download and run this DOS utility which will read the AMI/AWARD bios id string.
If you can't locate the manufacturer yourself from the CTBIOS information
then send WEB HQ the output. You can cut & past the info or redirect the
output to a text file and send it thru email. Create the TEXT file using this
DOS command line: CTBIOS.EXE >> WEBHQ.TXT
we strongly suggest you use this utility thats found on our Diagnostic Tools download page:
biosagent.zip 306kBios Agent 3.45 reports BIOS string, model#, chipset, cpu, memory
Accessing BIOS Setup
If you require the CMOS
Reset and don't have the proper jumper settings try these methods:
Our Help Desk receives so many requests on clearing
BIOS/CMOS Passwords that we've put together a standard text
outlining the various solutions.
Take note that resetting the CMOS settings may cause the motherboard to
revert to a default password on some boards. The password is usually Award, AMI, etc...see below
When clearing the CMOS, it's NOT done by pulling the lithium
battery or DALLAS chip off of the motherboard for a short period
of time. Instead, there is a jumper on the motherboard that
clears the CMOS. The jumper varies for all motherboards, so you
will need to see which jumper applies to your motherboard.
- Did you recently 'flash'
your computers BIOS, and needed to change a jumper to do so? Perhaps you
left the jumper in the 'flash' position which could cause the CMOS to be
erased. A system with a seeminly dead Bios might have actually been erased
by an incorrect 'flash' upgrade attempt.
Please Note: older 486 motherboards
did not have 'flash' support because it wasn't invented at that time. Its possible
to find and download 486 Bios binary upgrade files for these older boards but they require
the binary files to be 'burned' into an EPROM, and the PROM Writer costs over $900 US !!
Anyone attempting to 'flash' an non-flash motherboard will corrupt the Bios leaving the
motherboard completely unuseable...
don't believe me? come see the stack of boards we've
recieved over the years
- Its possible your system may have reverted to its default password.
Try these as passwords (case sensitive):
- If you still can't enter the BIOS Setup try these famous keystrokes:
- AMI BIOS: Del key during the POST
- DTK BIOS: Esc key during the POST
- Award BIOS: Ctrl-Alt-Esc
- misc BIOS: Ctrl-Esc
- Phoenix BIOS: Ctrl-Alt-Esc or Ctrl-Alt-S
- IBM PS/2 BIOS: Ctrl-Alt-Ins after Ctrl-Alt-Del
- Some 286 machines don't have a CMOS configuration menu in the BIOS.
They require a software CMOS setup program. If you don't have the
Installation and/or Diagnostics diskette for your machine, you can
try using a shareware/freeware program. Try looking in:
for example, http://www.simtel.net/pub/msdos/sysutl/gsetup31.zip
- If none of those passwords worked, look in your motherboard/PC's manual for a
jumper that will reset the CMOS. If you can't find it in the manual, look on your
motherboard and find the battery. There should be a jumper with three (3) pins
directly adjacent to the battery. To reset the CMOS Settings/Password, move the
jumper to the 2-3 position if it is currently 1-2, or 1-2 if it is currently 2-3,
wait 15 seconds, then turn the power on. Now, move the jumper
back to the original pins. Presto, no more password. There are numerous jumper
and pin configurations so becareful and contact us if you're in doubt.
- If you're unsure about the jumper, it may be necessary to remove the CMOS
battery. If the battery is not soldered to the motherboard, this should be an easy
task. With the computer's power off,
remove the CMOS battery (2032) and then short the battery connectors with
a 10k ohm resistor (brown,black,orange) for about 10 mins. Power up and enter
the BIOS Setup, if its now cleared power off and replace the battery then proceed as usual.
Also try setting motherboard jumper for an external battery and then
shorting those pins out works...by setting it to external it bypass's
- Here is an odd ball thats worked for us on old 486SX boards: remove the keyboard from
the system, some systems when powered up will default to the CMOS Setup if a keyboard is not found.
Some will Auto Enter the CMOS Setup and head right for the keyboard setting...
save using the mouse and reboot.
If that doesn't work, then turn off the computer, and unplug the keyboard.
After a minute or so, turn the computer back on. When you get a "keyboard error" on your screen,
plug the keyboard in (Yes, while the computer is on. It won't hurt the system.)
and then press the DEL/F10 key. This is a good trick for Compaq systems.
To reset the Bios when the password protection is enabled try using this DEBUG script.
Boot the system to a plain DOS prompt and type:
DEBUG ; Run DEBUG, "-" will appear on each line then type:
o 70 2e ; Send 70 to address 18
o 71 ff ; Send 71 to address FF
q ; Quit DEBUG
or you can use this alternate DEBUG script sent in by: email@example.com
DEBUG ; Run DEBUG, "-" will appear on each line then type:
o 70 20 ; Send 70 to address 18
o 71 21 ; Send 71 to address FF
q ; Quit DEBUG
Send in other useful DEBUG scripts. Let me know how you make out or if you find another solution...
We have expanded this area to include a useful utility,
please visit CMOS Pitfalls for more details.
American Megatrends Inc. (AMI)
AMI has been around for quite a while now and has earned itself a name (with me anyway!!!)
as one of the easiest to use BIOS's because of usually great documentation supplied by the
motherboard manufacturers. (These are admittedly USA and European manufacturers - but a
few 'Far East' companies (like Fujitech / Octek of Singapore) have excellent BIOS
your motherboard from an AMI BIOS is relatively easy if you take a look at the section
at AMI's site called just that!! You can also get a similar but slightly simplified
version of this page from Wim's BIOS
A lot of Intels' motherboards use the AMI BIOS and details about how they are identified (as well as some of the OEM's who use Intel motherboards) are in the Intel section below
Award state on their BIOS page - "Do not contact Award Software for BIOS upgrades
or BIOS technical support" - but a lot of useful information can be gleaned from
their Frequently Asked Questions (FAQ's)
on their Web site. They also have a how to identify your motherboard section from
an Award BIOS number for motherboard manufacturers worldwide. Again you can get a
similar but slightly simplified version of this page from Wim's BIOS Page
For all end-user technical support and BIOS upgrades for Award Software BIOS products
contact Unicore Software Inc.. Their e-mail address
Microid Research Inc. manufacture the MR BIOS for various chipsets and are available as
upgrades for most motherboards. If you have an Intel based pciset (formerly called
'Triton') click here to see if your
motherboard is included. If your pci chipset is NOT Intel then click here They also have a very informative Frequently Asked Questions (FAQ's) section.
A third party company handles MR BIOS upgrades
Identifying a Motherboard with a Phoenix BIOS could be difficult, the reasons being as
follows (quoted from Phoenix's FAQ's):
"If you cannot find the maker's name on or in the computer, in the copyright notice
displayed during POST, or in the owner's manual, then you are out of luck. Phoenix does
not make computer systems. There is no reliable way for Phoenix to determine the original
manufacturer. The numbers listed on the BIOS sticker on the motherboard do not identify
the BIOS version or the manufacturer of the system." They "are sequence numbers
used to count stickers. They do not identify the BIOS nor the computer manufacturer. Our
customer list is highly propriety information."
All is not lost however companies like Intel have upgrades for the
Phoenix BIOS's used on their motherboards.
Phoenix Technologies Homepage
Phoenix Technologies Technical
Motherboard Manufacturers BIOS Upgrades
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