Archived from groups: alt.comp.periphs.mainboard.asus (
More info?)
Hi.
The person who said that the onboard monitor is not accurate was
totally right.
I checked the voltages by opening the cabinet and using a digital
multimeter and found that the +5V value is about 4.95V with the PC
turned on but without working with it. This value dropped to 4.87V by
working doing several things at the same time (I started the virus
scan for my hard disk, opened a file from my CD-RW drive and asked my
scanner to scan one page).
As for the +12V value, I found that is about 12.66V in steady state
and increased to 12.92V by doing the above 3 things at the same time.
I have to say that everytime my PSU got damaged I was not making too
many tasks with the computer. Even once I was doing nothing. Just the
PC was turned on. Nothing else.
Somebody asked me if I see some damaged components or cables by
looking at it. I do not see anything wrong with the motherboard and
cables. When my PSUs failed in the past, nothing burnt, just the PSU
stopped working in one second.
What do you think? Should I measure anything else?
Adrian
nospam@needed.com (Paul) wrote in message news:<nospam-2704050409430001@192.168.1.178>...
> In article <ee91c56b.0504261024.7e1f3171@posting.google.com>,
> aegalperin@hotmail.com (Adrian Galperin) wrote:
>
> > Dear folks,
> >
> > Thanks for your replies.
> > I have checked with ASUS Support and they told me to download one ASUS
> > utility (ASUS PC Probe) for measuring some voltages. I found by using
> > this software the following values:
> >
> > +12V 12.544
> > +5V 4.73
> > +3.3V 3.328
> > Vcore 1.664
> >
> > As a result, ASUS support replied me:
> > "your +5V value is too low and the +12V value is too high; that means
> > your Power supply unit is not so good.
> > if possible ,i think you need test with another PSU, you can see the
> > every output value in the PSU label,
> > you need use a PSU with :
> > +5V higher than 28A,
> > +12V higher than 16A"
> >
> > I checked my current PSU and it is:
> > Output 350W
> > +3.3V 22A
> > +5V 25A
> > +12V 12A
> >
> > What do you think? Do you think the problem I am having (I already
> > damaged 3 PSUs) is because I need a better PSU which can achieve the
> > values recommended by ASUS Support.
> >
> > I would like to know your comments about this.
> >
> > Thanks.
> > Regards,
> >
> > Adrian
> >
>
> Well, I don't know if dwelling on the details of PSU design is
> going to help you resolve this problem or not. Occasionally, I
> run into reports here, where the symptoms suggest there is an
> internal fault in a motherboard, but the only way to determine
> if that is the case, is either by observing visual damage to
> some component of the system, or to measure the current flow.
>
> For example, I have seen a Vcore failure, where the area around
> the CPU socket was charred from the heat. I have also read a report
> of a power supply casing getting too hot to touch. Those are signs
> that something bad is happening, and would be cases where the
> current being consumed is way above either the ratings of the
> power connector or of the power supply itself.
>
> First, a little note about power supplies. I have a couple of
> different kinds here. The simplest kind has one feedback wire on
> a 3.3V signal. If you look at the ATX 20 pin wire harness, there is
> a 3.3V pin, which has one thick wire, and one slightly thinner wire.
> The thinner wire is a remote sense, and the power supply observes
> the voltage measured at the end of the thinner wire. You will
> notice that the value of the 3.3V output is very close to the
> correct value, and the sense wire helps make that possible.
>
> The older power supply designs had one primary circuit. One of the
> points to note here, is that some of the output voltages are
> determined by the transformer turns ratio, and are not that
> precisely regulated.
>
>
http://www.pavouk.comp.cz/hw/en_atxps.html
>
> Power supplies like the Antec Truepower have separated the outputs
> somewhat, and there is a sense wire for +3.3, +5, and +12V.
> This means the power supply outputs are separate stabilized.
> So, not all power supplies have the same internal architecture.
>
> Depending on the design, some power supplies have a limit on
> the combined total power coming from +3.3V and +5V. This may
> present a practical limit which is lower than the one listed
> as the maximum current on a winding.
>
> When I look at your voltages:
>
> +12V 12.544
> +5V 4.73
> +3.3V 3.328
>
> what they tell me is -
>
> 1) Your supply uses a single thin wire on a 3.3V power pin.
> The power supply is tightly regulating the 3.3V voltage.
> The +5V and +12V voltages are related to the 3.3V voltage
> by means of the fixed turns ratio of the output transformer.
>
> 2) The +12V is higher than normal.
> 3) The +5V is lower than normal
>
> 4) Based on (2) and (3), what this tells me, is the +5V winding
> is quite heavily loaded, which is to be expected for your
> type of motherboard (Asus athlonxp motherboards power the
> processor from +5V). Comparatively speaking, the +12V is
> not being loaded nearly as much, so its voltage runs higher
> than normal. I am more concerned with the 4.73 number, than
> with the +12V going a little high.
>
> The +5V reading of 4.73 is at the lower limit of the usual
> 5% tolerance listed on the label on the supply. That means
> the number of amps flowing must be getting in the neighbourhood
> of the capacity of the power supply.
>
> So, what to do about it:
>
> 1) Buy a "boat anchor". For example, this power supply claims to
> be able to provide +5V @ 61 amps, which is not physically
> possible. It costs $64 US, and is not the most expensive
> power supply you could buy. (It isn't really a 61 amp
> supply, because the combined output limit on +3.3 and +5V is
> 235 watts, and even if the current flowing on the +3.3V output
> is 0 amps, the +5V can make 47 amps.) This power supply will
> teach your motherboard who is the boss
🙂
>
>
http://www2.newegg.com/Product/Product.asp?Item=17-101-406&depa=0
> VOLTAGE +5V +12V +3.3V -5V -12V +5VSB
> PSP4ATX50F 61A 28A 35A 0.5A 0.5A 2A
>
> 2) Buy a separately regulated supply. Any of these Antec
> Truepower supplies will do the job. The True380 may be
> enough current for +5V, to avoid problems. A True550 would
> cost too much to be practical. There are some other brands
> that also separately regulate the outputs, like OCZ 420ADJ
> (http://www2.newegg.com/Product/Product.asp?Item=N82E16817104150)
> where adjustment knobs are provided for each power rail. There
> might even be an Enermax that does that.
>
> VOLTAGE +5V +12V +3.3V -5V -12V +5VSB
> TRUE330 30A 17A 28A 0.5A 1.0A 2.0A
> TRUE380 35A 18A 28A 0.5A 1.0A 2.0A <--- $65 US
> TRUE430 36A 20A 28A 0.5A 1.0A 2.0A
> TRUE480 38A 22A 30A 1.5A 1.0A 2.0A
> TRUE550 40A 24A 32A 0.5A 1.0A 2.0A <--- $95 US
>
> 420ADJ 30A 30A 28A 0.5A 0.5A 2.0A <--- $89 US
>
> 3) Buy an efficient supply. When your motherboard draws more power
> than it should, a supply like this will not get nearly as
> hot internally. Only problem with some of these, is they
> are way too expensive. So, I think the "boat anchor" brute
> force approach may be more economic than the elegance of
> a high efficiency supply.
>
>
http://www.tomshardware.com/howto/20050228/power_supply-37.html
>
> 4) Get another motherboard ? Like maybe Abit NF7-S (I've heard
> comments that the S2/S2G is not quite as nice, so read up
> on which one is the best one to get). The NF7-S family run
> the processor from +12V, at a lower current. The NF7-S has
> likely been out of production for some time, leaving only
> the S2 and S2G in the retail channel.
>
> http://www.abit-usa.com/products/mb/
>
> HTH,
> Paul