VOGONS


First post, by appiah4

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I came into possession of a 75MHz FSB Cyrix mII 300GP 75MHz. I'm not comfortable with overclocking the PCI/IDE, so I was wondering if I could just use 66MHz FSB but up the multiplier to 3.5x as on the regular mII chips?

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Reply 2 of 7, by appiah4

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canthearu wrote:

Cyrix MII processors are FSB and Multiplier unlocked.

Just set whatever parameters you want.

Excellent, many thanks.

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Reply 3 of 7, by feipoa

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3.5x works, but if you try to use 4x, many socket 7 motherboards won't work with this unless the BIOS is modded to specifically support 4x. Most super socket 7 boards should be fine though.

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Reply 4 of 7, by lazibayer

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feipoa wrote:

3.5x works, but if you try to use 4x, many socket 7 motherboards won't work with this unless the BIOS is modded to specifically support 4x. Most super socket 7 boards should be fine though.

I found your last year's post about getting 4x multiplier on MII. The databooks I could find only list inputs from CLKMUL0 and CLKMUL1. Could you please share your version of the MII databook? Thanks.

Reply 5 of 7, by feipoa

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These are just a few of the documents for the MII.

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Reply 6 of 7, by feipoa

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I find the discussion on trace capacitance, trace reflections, restive dampening, and diode clamping interesting. It is on the first few pages of CyrixMII_-_MII_100MHz_Bus_Design.pdf

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