I did. One RTAI is not a good reference, and the P4 needs a ton of thermal protection because it will literaly burn/melt itself. Other processors from both Intel and AMD use a hardware limit to keep the processor from killing itself, the software limit (SMM) is used to down/up clock the CPU to further control Thermals. SMM is a bad idea still because you can disable it, or it can fail to run. You should know that software can not be trusted, and can/will fail without reason.
Laptops use an Embedded Controller for various functions in addition to replacing the SMM Thermal Protection with a hardware-based Thermal Controller.
PS. I do hardware design and work on Coreboot, so I actually understand how and what goes on with hardware and Firmware.
Hmm. I'm not a big fan of flashing your BIOS while an operating system is running on top of it either. If you have any kind of power management running chances are pretty good that there are occasional calls into the BIOS happening... and if one of those calls happens while the BIOS ROM is blank, that would be a problem.
I wouldn't flash the BIOS under any OS unless I already had a recovery plan - either a disk or a shadow BIOS stored in the flash.
The bios image in the flash is read out at boot, parts of it are executed in situ, parts of it are copied/extracted to ram and then executed, and the parts that are needed later are kept around in C,D,E and F segments, with the necessary hooks installed in the interrupt vectors and the EBDA. So whatever you need at runtime no longer depends on the contents of the flashchip.
Stop spreading useless FUD about real free software.
Backup plan when it fails under linux: make sure you don't reboot or power-off and contact the developers right away (on irc or on email).
If you do mess up and have a socketed bios, you can find someone to flash your bios for you or you can buy a new pre-flashed chip off of ebay for an arm and a leg.
It is clear where you stand against BIOSes and all that surrounds them, and it is clear why. Equally it is clear where i stand, and why i stand there: because i have been dealing with them all my time as a free software developer and only found them to be: buggy/hard to fix, and forcing solutions which are not as good as they can be, which are full of workarounds. Don't dare claim anything else.