Do BIOS Upgrades Really Matter?

inkfox asks: "It seems that whenever one buys a motherboard, there's already a BIOS upgrade available by the time you get your hands on it, usually dealing with some degenerate hardware behavior. Given that Linux and Windows 2000/XP replace all BIOS routines once loaded, do these upgrades really matter? If a system is successfully booting, is a BIOS upgrade more a risk than it is preventive maintenance?" This may be true, but what if you are running an OS that depends on the BIOS? If the BIOS is replaced by a specific OS, then BIOS upgrades can't really hurt anything, can they?

Comments

Re:More than just code

[sigwinch]

If you're having PROBLEMS with something, by all means upgrade, even if you don't think your OS is actually calling any code in the BIOS.

There's something called System Management Mode used by many modern motherboards, where the CPU is periodically interrupted and runs code from the BIOS. Motherboard designers use it for all kinds of stuff: emulating the keyboard controller, monitoring CPU temperature, etc. In general there's no way to know what SMM is used for; the OS just has to get out of the way and pray.

OS designers generally regard SMM as a dangerous kluge, and think that the tasks would be better done using a microcontroller integrated into the chipset. The problem is that (brain-damaged) motherboard designers don't see it that way...