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Just wanted to pass along something I learned regarding dual BIOS.
Be aware that, if your primary BIOS gets corrupted, the MB will switch to the secondary BIOS. The secondary BIOS may not match your DSDT file, and this can cause problems if you don't notice that the switch has occured.
Some Gigabyte motherboards (like my P55M-UD2 have a dual BIOS feature whereby the motherboard has two boot ROM chips. The board is designed such that, if the primary BIOS is corrupted, it reverts to the back-up BIOS. It's a good feature.
Often the two BIOS chips have different revision levels of the BIOS code. Mine has F11 (latest BIOS version) in the primary BIOS, and F8 in the back-up. (Didn't plan it this way, it just happened).
What happened on my system was this: I was experimenting with overclocking, and the primary BIOS got corrupted. The motherboard reverted to the back-up BIOS. My DSDT file was for the code in the primary BIOS. I didn't notice that the MB had reverted to the secondary BIOS which had an older version of code. A few things on my system suddenly stopped working (e.g., the CMOS reset fix).
The fix was simple - I reflashed the primary BIOS.
I don't know how to force the primary and secondary BIOS files to match. I think Gigabyte might intend for them to be deliberately at two different levels.
Be aware that, if your primary BIOS gets corrupted, the MB will switch to the secondary BIOS. The secondary BIOS may not match your DSDT file, and this can cause problems if you don't notice that the switch has occured.
Some Gigabyte motherboards (like my P55M-UD2 have a dual BIOS feature whereby the motherboard has two boot ROM chips. The board is designed such that, if the primary BIOS is corrupted, it reverts to the back-up BIOS. It's a good feature.
Often the two BIOS chips have different revision levels of the BIOS code. Mine has F11 (latest BIOS version) in the primary BIOS, and F8 in the back-up. (Didn't plan it this way, it just happened).
What happened on my system was this: I was experimenting with overclocking, and the primary BIOS got corrupted. The motherboard reverted to the back-up BIOS. My DSDT file was for the code in the primary BIOS. I didn't notice that the MB had reverted to the secondary BIOS which had an older version of code. A few things on my system suddenly stopped working (e.g., the CMOS reset fix).
The fix was simple - I reflashed the primary BIOS.
I don't know how to force the primary and secondary BIOS files to match. I think Gigabyte might intend for them to be deliberately at two different levels.
