adding vcore voltage change support to a bios

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Keeper
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Hello! :D

I've noticed this site while wondering around on the internet, looking for some answers on how to change the vcore voltage on my FIC VB-601 motherboard, since it supports multiplier change and also FSB change but not vcore voltage change. I've read tons of posts on the forum, but i couldn't find any answer regarding this subject...so here i go:

My hardware specs are :

-> FIC VB-601 version 1.4, with the latest bios (MI4118) (award BIOS)
-> Pentium II Klamath 300mhz @ 2.8 Volts

...modding the voltage on the CPU itself, seems quite hard has explained in here : http://fermi.ruc.dk/~hkt/p2volt/ :cry:

...and modding the board itself, i couldn't find any link nor information, regarding vcore voltage modification... :cry:

My last hope is that you guys can help me out somehow, explaining to me if it's possible (or not) to add a bios function that allows me to change the vcore voltage of the cpu, and what tools/how to do it/what code to insert, if possible... :D

I've used awdbedit with the hope that some vcore function would be there but hidden, with no luck...

Can any of you help me out please ?



Thank You,

Keeper 8)
Denniss
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Not possible .
The Bios has to control VCore change via direct connections to the Voltage chip and without a connection that's not possible .
And the Klamath should get very hot if you overvolt him .

Have you tried to lower the multiplier and raise the FSB ?
I have a 266 running fine at 3x100
Keeper
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Yes..i've tried alot of things with the multiplier..:

4.5 x 66 fsb (~300 mhz - works - default)
4.0 x 75 fsb (300 mhz - works)
3.5 x 83 fsb (~290 mhz - works)

3.0 x 100 fsb (300 mhz - a little unstable)
3.0 x 103 fsb (309 mhz - a little unstable)

3.0 x 112 fsb (336 mhz - BSOD on windows)
4.0 x 83 fsb (~333 mhz - BSOD on windows)
4.5 x 75 fsb (~337 mhz - BSOD on windows)

3.0 x 133 fsb (~400 mhz - PC doesn't boot)
4.0 x 100 fsb (400mhz - PC doesn't boot)


note: This memory stick is a 256mb@133mhz from compaq.



...so, has you can see, any multiplier/fsb pair, that makes the CPU go over the 300mhz barrier, generates instability/crash on the system.

My conclusion is that the problem resides on lack of voltage..so i think..it can also be a problem with the AGP bus voltage..or even both.

The only thing that i find strange in all this, is that at 300 x 100 fsb, the PC starts to crash after sometime, though the memory stick supports up to 133mhz..


I'm just doing this OC, due to the reason that i just need about 10~12% more of CPU power, to be able to watch my divX movies at the normal speed (25frames/sec). And supposedly, this CPUs have that margin..

My video card (Riva TNT 2 Ultra) is OC'ed at 200mhz core / 220 mhz dram, way behond the defaults (150/183) and working perfectly. I'm just saying this in case you thought on overclocking it to solve my "issue"..


If you or someone else could give me a link on how to overclock the voltage on the klamath (or how to solve this), i would apreciate.


Thank you,


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Denniss
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It's very hard to overclock a Klamath to more than 300 MHz and it needs very good cooling .
More VCore should not help to overclock - it makes this hot CPU heating up your case very fast .

A little unstable at 100MHz Operation might come from FSB overclock(CPU does not like the high I/O bus) or a mainboard/memory thing
Ritchie
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Joined: Wed Oct 30, 2002 5:17 am

Applying extra voltage will cause a CPU to overheat.

I think Denniss is saying that overclocking, even without applying extra voltage, will also cause a CPU to overheat. Therefore I would stay away from overclocking.

However I noted your settings to attempt to overclock the CPU mostly relied on faster FSB speeds. For a faster running speed, you will require the appropriate RAM speed to match (PC100 or PC133). You may only currently have PC66 memory.


If I were you, I would avoid overclocking because of the overheating risk. Rather install a faster CPU and retire the existing CPU to a system required for less demanding tasks.
soupy
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Yep. Spend the $20 and get a PII-450 or even a PIII.
Flash your BIOS at your own risk.
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