The newer Durons used a new core and there isn't any known issue outside of the cosmetic issue. A motherboard maker might not update the BIOS if it just works.
Bob
Hi-
For some reason my BIOS is recognizing my Duron 1 GHz as an Athlon 1 GHz. I know there was a BIOS fix for this, but I cannot find it anywhere. I have checked Chaintech's website and they do not even list my board anymore. I have the latest VIA Chipset drivers for the KT133. My mobo is a Chaintech 7AJA0-F100A (that's right off the sticker).
My current BIOS:
PhoenixBIOS D686
CTF9A25-2 V5.0 01/01/2001 6CBC
Any help would be appreciated. Thanks.

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