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Vcore voltage - what's it for and why increase it?

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maxima88

Member
Joined
Jan 24, 2002
I was just curious to know what the vcore really is and how does the increase/decrease of the voltage affect a system's performance and stability.
The reason I ask is I'm about to mod my K7S5A to increase my vcore from 1.74 to 1.85~1.95 (will be using a variable resistor).
Will this finally get my system to post at 150fsb. My system runs super stable at 146.6fsb but won't post at 150.
My 400W Antec 403PSU will be here on Thursday.
Hope this helps too.
 
vcore

cpu voltage has two states... on and off. When overclocked, it switches between these 2 states more quickly, eventually too fast, so that while the voltage is still transitioning between states it takes a reading and gets it wrong... ie reading an off state as an on state or vice versa. This causes miscalculations and instability. By increasing the vcore, the difference between these 2 states is greater and the transition, while not actually going faster, has a better chance for the cpu to read the correct voltage state becasue the on state peaks higher and is in the zone of what constitutes the on state for a longer period. So there's less chance it will read an on state as an off state.

Not a very clear explanation, but I read an article about it awhile ago. Gotta find the thread with a link for the article. Its much easier to understand with pictures and more in-depth explanation.
 
first it depends if ur ram and other parts in ur PC can handle 150 fsb then its if ur motherboard can handle 150 fsb then its vcore... i saw on the cpu database that the only way i could go higher on my crapy stepping 1.13 athlon was to get it at 2.05 vcore so i did a lot of reading learned how to do it and a new soldering iron and a 1 almost burned finger and i was done. not if u think u know how to solder and are ready then go for it the worst that can happen is that u will **** up ur whole motherboard burn ur fingers off maybe fry all ur parts and of course ur CPU ;) ok jk lets say a higher vcore cant get u to 150 fsb then screw it u have not gained or lost anything and now u can be proud to say u moded ur motherboard :D just make sure u know what u are doing!!! i tryed this on a old fryed motherboard off a cd rom drive first so i knew i could do it....
 
Here's a simpler explanation- Ohm's law states that the current in a circuit is proportional to the potential difference (volts) across the circuit. If a set resistor is used you have the equation V=RI
I=amps R=Ohms and R is the constant.
As the temps increase so does the value of the resistence. Since the voltage across the circuit is regulated (core voltage or vcore) and therefore constant this will result in drop in the current in the circuit. At a point there will be insufficient current to drive the system and instability will occur. By increasing the core voltage the current flow will be higher and therefore stability retained. The down side is that increased current will result in higher temps and so the loop goes on. That is why cooling becomes such a vital part of the equation as by reducing temps you can keep the resistance constant and therefore stable with less vcore.
 
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