VCORE STABILITY: Can we get an answer?

lopri

Elite Member
Jul 27, 2002
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FACT 1: For a successful overclocking, one of the most important factors is a stable voltage for the CPU.
FACT 2: You will never find a board with such a thing. Mobo manufacturers don't take kindly to such obscenity.


A typical scenario with a typical enthusiast motherboard regarding Vcore goes like:

  • 1. A user select a Vcore in the BIOS.
    2. Upon POST, the board feels the user's greediness and gives 0.05V less Vcore.
    3. Entering Windows, the board misses the target by ~0.02V but it knows the user will just deal with it.
    4. Once the user load the CPU, the alerted board goes into a power-saving mode and cut additional 0.04V.
    5. From there, the Vcore starts dancing up and down.
OK, this scenario might be exaggerated, but the point still stands. A seemingly high-end motherboard with decent build quality and many features, will still not meet the standard of an enthusiast as far as Vcore is concerned. We now even have a term describing this common issue - Vdroop/Vdrop. Icing on the cake is the Vcore fluctuation.

I've heard various rumors including a conspiracy theory with this matter, but now I want a legitimate answer. Why can't they get it right? Many boards DO get other voltages right. And on many occasions they actually overvolt things. EXCEPT THE CPU. I'm getting tired of Vdrop, Vdroop, Vcore fluctuation and want to know what is really going on.

If anyone has a piece of knowledge, please chime in!
 

Duvie

Elite Member
Feb 5, 2001
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My Gigabyte DS3 mobo was tight with my C2Ds....I set 1.45v in the bios and it is 1.44v in windows and would drop to maybe 1.42-1.43v under load.....NOt much fluctation.......

Then I put my quad core into that board....Set it to 1.45v....enter windows at 1.39v and load to 1.36v....whopping .09v drop....
 

myocardia

Diamond Member
Jun 21, 2003
9,291
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DFI makes the most stable boards, as far as voltage fluctuations. But, no board or power supply can be dead-on. I asked my friend about it, about 4 or 5 years ago, and he explained it to me. Oh, he's an engineer at Intel. He's a senior engineer there, as a matter of fact. He said that the stronger the power supply (both the system psu, and the power supply/supplies on the board), the less the drop. But, he said that it's completely impossible to use amperage anywhere, with anything, and the voltage not drop to some extent.

My dad, who retired from the electric company in Dallas, and who was an "operator" (the guy who ran the actual generator) said the same thing. As a matter of fact, my dad also said that if everyone in Dallas were to shut everything in the city that used electricity off at the same time, that the voltage in the lines (the available electricity, that's now not being used) would skyrocket.

edit: And like Duvie just said, the more amperage you use, the lower the voltage will drop. It's because of Ohm's law.
 

lopri

Elite Member
Jul 27, 2002
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I'm aware of what you guys pointed out. It certainly makes sense but at the same time, mobo manufacturers must be aware of that, too? I mean, think about these:

1. They seem to get voltages for other components pretty well, regardless of the load. For instance, memory and chipset voltages are pretty much spot on from the boot to 100% load in Windows. There are overvoltages/undervoltages to a degree, but nothing like Vcore drop/fluctuation.
1. They've been touting better power management for quite some time. 6 phase, 8 phase, and even 12 phase VRM? What for? DFI got it almost right just with 3 phase for their LanParty NF4 series.
2. Today's CPUs consume less power than ever (OK, not ever, but in recent history), which makes me think it should be even easier to regulate voltages for CPUs.