How do I know what my max Voltage is?

Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

I did a quick look in my manual (paper one included with my ASUS A8V
Deluxe, Ver. 2 Circa December, it has a BIOS "1009" on it I think, because
that is what it says on the EEPROM sticker) and I only saw one reference,
on page 4-28 where it says DDR options: "[auto] [2.6] [2.7] 2.8]". Does
that mean that I can't raise my memory voltage to 3 volts, or higher?

Does that option change with newer BIOS versions?

What about my CPU max voltage, what is it, and is that controlled by the
BIOS version (my understanding is that it is with some limitation).

If I update to version 1013/1014 beta, then what will my max voltages be
for my system RAM and my CPU?

Can someone help illuminate this for me?
4 answers Last reply
More about voltage
  1. Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

    In article <1mzjs5uhzdzve.1df87203pywpt$.dlg@40tude.net>,
    signmeuptoo@earthlink.net wrote:

    > I did a quick look in my manual (paper one included with my ASUS A8V
    > Deluxe, Ver. 2 Circa December, it has a BIOS "1009" on it I think, because
    > that is what it says on the EEPROM sticker) and I only saw one reference,
    > on page 4-28 where it says DDR options: "[auto] [2.6] [2.7] 2.8]". Does
    > that mean that I can't raise my memory voltage to 3 volts, or higher?
    >
    > Does that option change with newer BIOS versions?
    >
    > What about my CPU max voltage, what is it, and is that controlled by the
    > BIOS version (my understanding is that it is with some limitation).
    >
    > If I update to version 1013/1014 beta, then what will my max voltages be
    > for my system RAM and my CPU?
    >
    > Can someone help illuminate this for me?

    To start with, a voltage setting cannot go higher than the hardware
    design allows for. For example, the DIMM voltage on some Asus boards,
    is done with an op-amp based linear regulator, and in fact there aren't
    even three settings in the hardware (perhaps there are two). So,
    while the BIOS may offer a comforting set of values, the hardware
    doesn't necessarily have to match. In your example above, maybe both
    the 2.6 and 2.7 setting result in 2.6V output - only observation with
    any hardware voltage monitoring, is going to tell you what is happening.
    Since Vdimm is not one of the monitored voltages on your board, you
    would need a voltmeter to measure the actual voltage being used.

    The Vcore situation is a bit different, because a standards compliant
    switching regulator is used. If AMD defines 0.8 to 1.55V as the range
    of voltages for the K8 family, then that is the range that will be
    supported by the chip. If Asus offers voltages outside that range,
    it could be achieved by means of fooling around with an offset pin
    on the regulator chip, to adjust the voltage upward. Again, use the
    voltage monitor in the BIOS or Asus Probe, to know whether anything
    is actually happening when a higher voltage is selected. (I must
    confess that I'm puzzled how all this can work, because you would
    want programs like clockgen, CPUZ, NVtune, all sorts of Windows
    utilities to return valid voltage values, and I don't know how
    you can extend a Vcore circuit voltage range, and allow utilities
    like that to accurately reflect the setting.)

    So, to start with, you need to reverse engineer the chips on the
    motherboard, to understand the hardware limits. The BIOS is just
    another layer of confusion added on top, as the BIOS may or may
    not be reflecting what the hardware can do.

    As a general rule, don't expect a BIOS update to offer new voltages.
    I think I have seen one BIOS released by Asus, that added a voltage
    value to the BIOS interface, so it can happen, but it is not a
    common occurrence.

    The hardware itself has limits. 2.8V is probably considered a
    safe generic overvoltage for your average DIMM, so Asus doesn't
    consider that they will be liable if any user burns out a DIMM.
    If you had a DFI board that offered 4.0V, there is every
    possibility that either through a BIOS bug (value gets set to
    4V by a BIOS bug), or a noob user jamming the control to max,
    will result in the killing of DIMMs. I'm sure DFI has plenty of
    disclaimers, that whatever you do, it is your fault.

    Asus is more conservative, and tends to pay attention to the spec
    limits for hardware. For example, the Athlon64 has a max DIMM voltage
    of 2.9V, so don't expect Asus to provide voltages above that
    value. (I don't know of a way to predict the headroom that is
    actually available on Vdimm - it really depends on I/O protection
    structures, and it can also depend on how the various power
    rings are connected together by parasitic structures inside the
    chip. When boosting a voltage to artificially high values, you could in
    fact be causing current to flow through paths in the chip,
    that is wasn't intended to go through - parasitic paths
    are ones that are created by using conditions outside the operating
    voltage specs.)

    Various private forums on the net, offer volt mods for Vdimm and
    Vcore. If you are determined to "go to the wall", that is one
    way to get what you want. Or, perhaps a DFI or Abit motherboard
    is the way to go.

    Wire tricks (placing a wire between certain pins in the socket),
    only helps if the Vcore defined for the processor has some range
    left in it. If the K8 VID table only goes to 1.55V, then a wire
    trick cannot offer more than 1.55V. An actual volt mod can do it,
    but is dangerous - this thread proves you should do mods to your
    own board, not let someone else do it:

    http://www.xtremesystems.org/forums/showthread.php?t=40378&highlight=a8v

    The purpose of Asus boards, is to offer broad compatibility with
    stuff like DIMMs, and easy out-of-the-box auto-everything setup
    by the user. Asus boards are not the optimum solution, if you
    also want to overvolt (or undervolt) stuff.

    HTH,
    Paul
  2. Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

    On Sat, 11 Jun 2005 13:12:45 -0400, Paul wrote:

    > In article <1mzjs5uhzdzve.1df87203pywpt$.dlg@40tude.net>,
    > signmeuptoo@earthlink.net wrote:
    >
    >> I did a quick look in my manual (paper one included with my ASUS A8V
    >> Deluxe, Ver. 2 Circa December, it has a BIOS "1009" on it I think, because
    >> that is what it says on the EEPROM sticker) and I only saw one reference,
    >> on page 4-28 where it says DDR options: "[auto] [2.6] [2.7] 2.8]". Does
    >> that mean that I can't raise my memory voltage to 3 volts, or higher?
    >>
    >> Does that option change with newer BIOS versions?
    >>
    >> What about my CPU max voltage, what is it, and is that controlled by the
    >> BIOS version (my understanding is that it is with some limitation).
    >>
    >> If I update to version 1013/1014 beta, then what will my max voltages be
    >> for my system RAM and my CPU?
    >>
    >> Can someone help illuminate this for me?
    >
    > To start with, a voltage setting cannot go higher than the hardware
    > design allows for. For example, the DIMM voltage on some Asus boards,
    > is done with an op-amp based linear regulator, and in fact there aren't
    > even three settings in the hardware (perhaps there are two). So,
    > while the BIOS may offer a comforting set of values, the hardware
    > doesn't necessarily have to match. In your example above, maybe both
    > the 2.6 and 2.7 setting result in 2.6V output - only observation with
    > any hardware voltage monitoring, is going to tell you what is happening.
    > Since Vdimm is not one of the monitored voltages on your board, you
    > would need a voltmeter to measure the actual voltage being used.
    >
    > The Vcore situation is a bit different, because a standards compliant
    > switching regulator is used. If AMD defines 0.8 to 1.55V as the range
    > of voltages for the K8 family, then that is the range that will be
    > supported by the chip. If Asus offers voltages outside that range,
    > it could be achieved by means of fooling around with an offset pin
    > on the regulator chip, to adjust the voltage upward. Again, use the
    > voltage monitor in the BIOS or Asus Probe, to know whether anything
    > is actually happening when a higher voltage is selected. (I must
    > confess that I'm puzzled how all this can work, because you would
    > want programs like clockgen, CPUZ, NVtune, all sorts of Windows
    > utilities to return valid voltage values, and I don't know how
    > you can extend a Vcore circuit voltage range, and allow utilities
    > like that to accurately reflect the setting.)
    >
    > So, to start with, you need to reverse engineer the chips on the
    > motherboard, to understand the hardware limits. The BIOS is just
    > another layer of confusion added on top, as the BIOS may or may
    > not be reflecting what the hardware can do.
    >
    > As a general rule, don't expect a BIOS update to offer new voltages.
    > I think I have seen one BIOS released by Asus, that added a voltage
    > value to the BIOS interface, so it can happen, but it is not a
    > common occurrence.
    >
    > The hardware itself has limits. 2.8V is probably considered a
    > safe generic overvoltage for your average DIMM, so Asus doesn't
    > consider that they will be liable if any user burns out a DIMM.
    > If you had a DFI board that offered 4.0V, there is every
    > possibility that either through a BIOS bug (value gets set to
    > 4V by a BIOS bug), or a noob user jamming the control to max,
    > will result in the killing of DIMMs. I'm sure DFI has plenty of
    > disclaimers, that whatever you do, it is your fault.
    >
    > Asus is more conservative, and tends to pay attention to the spec
    > limits for hardware. For example, the Athlon64 has a max DIMM voltage
    > of 2.9V, so don't expect Asus to provide voltages above that
    > value. (I don't know of a way to predict the headroom that is
    > actually available on Vdimm - it really depends on I/O protection
    > structures, and it can also depend on how the various power
    > rings are connected together by parasitic structures inside the
    > chip. When boosting a voltage to artificially high values, you could in
    > fact be causing current to flow through paths in the chip,
    > that is wasn't intended to go through - parasitic paths
    > are ones that are created by using conditions outside the operating
    > voltage specs.)
    >
    > Various private forums on the net, offer volt mods for Vdimm and
    > Vcore. If you are determined to "go to the wall", that is one
    > way to get what you want. Or, perhaps a DFI or Abit motherboard
    > is the way to go.
    >
    > Wire tricks (placing a wire between certain pins in the socket),
    > only helps if the Vcore defined for the processor has some range
    > left in it. If the K8 VID table only goes to 1.55V, then a wire
    > trick cannot offer more than 1.55V. An actual volt mod can do it,
    > but is dangerous - this thread proves you should do mods to your
    > own board, not let someone else do it:
    >
    > http://www.xtremesystems.org/forums/showthread.php?t=40378&highlight=a8v
    >
    > The purpose of Asus boards, is to offer broad compatibility with
    > stuff like DIMMs, and easy out-of-the-box auto-everything setup
    > by the user. Asus boards are not the optimum solution, if you
    > also want to overvolt (or undervolt) stuff.
    >
    > HTH,
    > Paul

    Paul, you read my mind, and you answered the questions in my mind perfectly
    and then some.

    Since this will be my first Post PIII build (if and when I get a good job
    to pay for the CPU, RAM, PS, etc., it will probably be good that I cannot
    go off the wall anyways. But I do hope that I get around to building
    another system in the future where I can do more advanced setting work. By
    then maybe I will know more about what I am doing, I hope!

    In any event, it now seems to me that I will be best off with TCCD RAM
    rather than BH-5. I am only worried that I won't be able to get any before
    they stop selling the stuff!

    OT: You sound like you either work/worked in either the semi-con or
    network or electronics industries, or all of them. I really envy your
    knowledge, if I can be anyone, I would like to aspire to be like you, for
    you are a real asset here, please don't ever leave.

    Tell me, do you participate in any of the other Usenet/forums?
  3. Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

    In article <1gym40s1eg0bb.1loa5ssmuzqi3.dlg@40tude.net>,
    signmeuptoo@earthlink.net wrote:

    >
    > Tell me, do you participate in any of the other Usenet/forums?

    No, I prefer as public a forum as possible. With a private
    forum, your postings could disappear tomorrow, at the whim
    of the admins.

    Paul
  4. Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

    On Sun, 12 Jun 2005 17:36:21 -0400, Paul wrote:

    > In article <1gym40s1eg0bb.1loa5ssmuzqi3.dlg@40tude.net>,
    > signmeuptoo@earthlink.net wrote:
    >
    >>
    >> Tell me, do you participate in any of the other Usenet/forums?
    >
    > No, I prefer as public a forum as possible. With a private
    > forum, your postings could disappear tomorrow, at the whim
    > of the admins.
    >
    > Paul

    I haver imagined that perspective, but I see the logic in it.
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