These hints may seem obvious, but you can never be too safe: Avoid flashing your BIOS in an electrical storm.
Protect your computer against power surges or brownouts with a UPS
(uninterruptible power supply).
Don’t let anyone walk over the power cord during the flashing operation.
Check twice that you are flashing your BIOS with the current version, and
then check again.Flashing Security
Another potential risk of flash BIOS is the danger of accidentally flashing the BIOS. As
long as an accidental operation completes and uses the same complete BIOS version,
there is no harm done. However, if an accidental flashing operation is interrupted or for
somereasonusesanolderorincompatibleversion,theresultisthesame,accidentornot.
To prevent an accidental flashing, some security features are available to block the
flashing operation. On motherboards that support flash BIOS, a jumper can be set to
disallow flash updates. With this jumper set, the case must be opened and the flashing
securityjumperremovedbeforetheBIOScanbeflashed.Ifthisjumperisused,thereisno
way an accidental flashing can occur. A side benefit to the flash security jumper is that it
also prevents attacks from the new breed of computer viruses that attempt to change the
code of a flash BIOS.The Boot Block
The boot block does not block the boot. In fact, it does just the opposite. Theboot blockfea-
ture, which is showing u pon the newest motherboards, recognizes the risk of a flashing
operation corrupting the BIOS. The boot block works very much like the switch now
included in newer cars to start a car when its battery goes dead. It is a 4KB program block
that is included on the BIOS ROM that recovers a corrupted BIOS by restoring it from a
special disk supplied by the BIOS provider. If a motherboard supports this feature, it may
need to be enabled through a jumper. If you are planning to upgrade your BIOS with
flashing,youmaywanttocheckyourmotherboard’sdocumentationforthisfeaturefirst.(^128) PC Hardware: A Beginner’s Guide