How to know if your CPU is unlocked and supports multiplier control? \ VOGONS

How to know if your CPU is unlocked and supports multiplier control?

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First post, by DustyShinigami

Posted on 2026-01-19, 19:08

DustyShinigami Offline

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Like the question asks... I just got my Pentium II and I was under the impression it was unlocked based on its model name, but was very disappointed to learn that all the CPU throttlers I have say multiplier adjustment isn't supported. 🙁 Is multiplier unlocking with these older CPUs just down to luck? I'd read that the PIII's are generally locked, but was under the impression the II's weren't...?

This is the model I have: https://www.cpu-world.com/sspec/SL/SL2HE.html

OS: Windows 98 SE
CPU: Slot 1 Pentium III Coppermine 933MHz (SL448)
RAM: Kingston 256MB 133MHz
GPU: Nvidia 16MB Riva TNT/128MB Geforce 4 Ti 4200
Motherboard: ABit AB-BE6-II Intel 440BX
Sound Card: Sound Blaster Live Value CT4670

Reply 1 of 5, by paradigital

Posted on 2026-01-19, 19:48

paradigital Offline

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Only some of the earliest PII steppings were unlocked, most are locked.

Reply 2 of 5, by RetroPCCupboard

Posted on 2026-01-19, 20:04

RetroPCCupboard Offline

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I dont think the multipliers on the PII can be changed in software. It would be either jumpers on motherboard or a BIOS setting.

If yours is Klamath core, as per your link, then I think it is not hardware locked multiplier

Reply 3 of 5, by DustyShinigami

Posted on 2026-01-19, 20:14

DustyShinigami Offline

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RetroPCCupboard wrote on 2026-01-19, 20:04:

I dont think the multipliers on the PII can be changed in software. It would be either jumpers on motherboard or a BIOS setting.

If yours is Klamath core, as per your link, then I think it is not hardware locked multiplier

Hmm. So, do the jumpers need to be set a certain way on the motherboard for it to be unlocked? Or can it only be adjusted via the jumpers and that's it? The multiplier can be adjusted in the BIOS, but the lowest is 3.

Reply 4 of 5, by gerwin

Posted on 2026-01-19, 23:11

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RetroPCCupboard wrote on 2026-01-19, 20:04:

I dont think the multipliers on the PII can be changed in software. It would be either jumpers on motherboard or a BIOS setting.

If yours is Klamath core, as per your link, then I think it is not hardware locked multiplier

you are correct on both points.
The multiplier can only be requested at bootup (BIOS or Jumpers). After that brief time window, the request channel is closed.

--> ISA Soundcard Overview // Doom MBF 2.04 // SetMul

Reply 5 of 5, by DustyShinigami

Posted on 2026-01-19, 23:47

DustyShinigami Offline

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Thanks for clarifying. 😀

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