Can a Pentium III be forced to identify as a Pentium II? \ VOGONS

Can a Pentium III be forced to identify as a Pentium II?

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First post, by SRQ

Posted on 2017-03-30, 05:39

SRQ Offline

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Alright so this project is no doubt stupid but I'm curious- is there a way to, at the firmware level, force a PIII 450 to ID as a PII 450? Simply for dating purposes- I want this rig to be PEAK 1998 and have no Pentium Its, but I have two PIII 450s. Which, as I understand, is just a PII 450 with SSE added.

Reply 1 of 4, by spiroyster

Posted on 2017-03-30, 06:43

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No, the CPUID (which is used by programs to identify the CPU) is embedded as an opcode. You can't change it or flash it or anything.

Reply 2 of 4, by SRQ

Posted on 2017-03-30, 07:03

SRQ Offline

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Dang darn.
Also, interesting, this SE440BX board reports a P3 450 correctly as a Pentium III despite it being released later (and this is default bios), but a 733 as a "to be announced."
I wonder, was Coppermine going to use a different name?

E: If anyone sees this, is a PIII 450 high end for 1999? I'm kind of dorky, it's not so much speed but "High end for X period."

Reply 3 of 4, by firage

Posted on 2017-03-30, 07:22

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Yes, they were high end for existing applications in the first half of the year, but not for long. The 500 MHz part came out at the same time and they were available in systems in March. Technically the fastest CPU's available at the end of the year were the 733 MHz (or even 800 MHz, theoretically) Coppermine and 750 MHz Athlon.

My big-red-switch 486

Reply 4 of 4, by Tetrium

Posted on 2017-03-31, 11:38

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You 'could' use a BIOS which predates PIII, it might recognize the P3 as a P2. Dunno if it will fool programs like CPUID though but you'd have the POST screen mention PII 450MHz. I've seen it happen on newer boards also, might even have been a C3 that was identified as an unknown P2.

Or use a modified BIOS file and flash that?

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