You should be just fine. Perhaps the appropriate statement from IWill should have been "added OFFICIAL support for AMD 1.4GHz" . As long as you set the jumper on the motherboard to support a 133MHz FSB (and have PC-133 RAM), it will work. The 0515 BIOS added support for a 14X multiplier, which would be required to run 1.4GHz on a 100Mhz FSB. However at 133MHz FSB the multiplier is 10.5, which is within the older BIOS capabilties. Your system should BOOT fine and allow you to use the BIOS of choice (barring other issues).
I would shy away from the 0515 BIOS, as it has issues with Re-booting in cycles rather than shutting down under Win2000/Win9X. The 0622 BIOS has the offical 1.4GHz support and 14X multiplier and does not have the "re-boot" problem.
You've settled on a GREAT MOBO !! Have Fun !!
God Bless America!
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