 |
 |
What is the EEPROM, EPROM, PROM on my video card?
|
Are the acronyms confusing? try the Glossary of computer terms |
For chipset information, go Here
|
A PROM (Programmable Read Only Memory) chip can be used to store video BIOS
code and/or video configuration information. All modern video cards have a
video BIOS, while many (but not all) store video configuration data right
on the video card.
Usually, EPROM's or PROM's (the 'E' indicating that the PROM is erasable or
'reprogrammable') are used to store the video BIOS. The BIOS consists of
code which the computer uses to communicate with the video card.
Occasionally when a bug is discovered in the video BIOS of a card, the card
manufacturer will supply updated ROM's that contain corrected video BIOS code.
Swapping of the new chip for the old is quite easy and safe, as long as the
machine is powered off and appropriate electrostatic precautions are taken.
EEPROM's (Electronically Erasable PROM's) are used on some video cards to
store video mode configuration information. These cards usually require
the user to run an installation program initially to determine the correct
screen refresh rate for the monitor at each screen pixel addressibility used.
Whenever the video card receives a request from the computer to switch video
modes, the card checks its EEPROM so that it can generate the video signal
at the correct vertical refresh rate. Information such as horizontal and
vertical centering and size can also be stored by some cards.
|
|