Voltage fluxuations on the -12 side GA7VM400M

I was trying to run a new XP2600+ on a GA7VM400M (Rev 1). When it would
startup I would get a voltage warning on my monitoring SW (I can't remember
the name of it.... it is a good one... names escape me...) It showed the
+12 side at 12.5 or 12.6V. The -12 voltage, however, was running
on the low side 3 to 6 volts (and fluxuating). I have never seen that
before. I did double check and noticed that the Antec P/S (known good) was
only 300Watts, but I was only trying to run:

XP2600+ on a GA7VM400M mobo
Win98SE
Sony CD R/RW
1 floppy
1 Maxtor 120 Gb drive (7200 RPM)

It came all the way up into Windows. I could even silence the alarm and do
stuff if I had wanted to.

I had a 420 Watt, high quality P/S in another system I was putting together,
but I don't recall ever actually testing this P/S. I bought it ($35 or $40)
and didn't get around to using it. Anyway, it would only cause the sysem
(fans, lights, etc) to run for a fraction of a second and then it would be
dead quiet.
Would the odd voltage indications be indicative of bad voltage regulators or
just an underpowered power supply (and a bad 420 Watt unit)? I did get the
board used... but from a guy I've known for years who has only sold me good
parts.

I initially only thought I was having thermal problems, but once I put a
GOOD (non AMD) cooler on there, I have had time to look at the rest of the
monitoring data and worried about the voltage.

TIA
KWW

KWW wrote:
I was trying to run a new XP2600+ on a GA7VM400M (Rev 1). When it
would startup I would get a voltage warning on my monitoring SW (I
can't remember the name of it.... it is a good one... names escape
me...) It showed the +12 side at 12.5 or 12.6V. The -12 voltage,
however, was running
on the low side 3 to 6 volts (and fluxuating). I have never seen that
before. I did double check and noticed that the Antec P/S (known
good) was only 300Watts, but I was only trying to run:

Don't concern yourself with the -12V readings. The +12V line is important. A
300W Antec should be fine, with the hardware you list below.


XP2600+ on a GA7VM400M mobo
Win98SE
Sony CD R/RW
1 floppy
1 Maxtor 120 Gb drive (7200 RPM)

It came all the way up into Windows. I could even silence the alarm
and do stuff if I had wanted to.

I had a 420 Watt, high quality P/S in another system I was putting
together, but I don't recall ever actually testing this P/S. I
bought it ($35 or $40) and didn't get around to using it. Anyway, it
would only cause the sysem (fans, lights, etc) to run for a fraction
of a second and then it would be dead quiet.

If you bought a PSU for $35-40USD, I have my doubts about it being a high
quality unit.

Actually, I found the price info on the P/S. $55. It is a Turbolink CWT
420ATX. I am going to check it out on another system.

OK about the -12 being unimportant, but why, then, did the warning SW flash
red and alarms go off? Just spooky...
Thanks,
--
KWW

"S.Heenan" wrote in message
news:OnNlc.366968$oR5.250946@pd7tw3no...
KWW wrote:
I was trying to run a new XP2600+ on a GA7VM400M (Rev 1). When it
would startup I would get a voltage warning on my monitoring SW (I
can't remember the name of it.... it is a good one... names escape
me...) It showed the +12 side at 12.5 or 12.6V. The -12 voltage,
however, was running
on the low side 3 to 6 volts (and fluxuating). I have never seen that
before. I did double check and noticed that the Antec P/S (known
good) was only 300Watts, but I was only trying to run:

Don't concern yourself with the -12V readings. The +12V line is important.
A
300W Antec should be fine, with the hardware you list below.


XP2600+ on a GA7VM400M mobo
Win98SE
Sony CD R/RW
1 floppy
1 Maxtor 120 Gb drive (7200 RPM)

It came all the way up into Windows. I could even silence the alarm
and do stuff if I had wanted to.

I had a 420 Watt, high quality P/S in another system I was putting
together, but I don't recall ever actually testing this P/S. I
bought it ($35 or $40) and didn't get around to using it. Anyway, it
would only cause the sysem (fans, lights, etc) to run for a fraction
of a second and then it would be dead quiet.

If you bought a PSU for $35-40USD, I have my doubts about it being a high
quality unit.

KWW wrote:
Actually, I found the price info on the P/S. $55. It is a Turbolink
CWT 420ATX. I am going to check it out on another system.

OK about the -12 being unimportant, but why, then, did the warning SW
flash red and alarms go off? Just spooky...

CWT=ChannelWell Technology At one time they made power supplies to Antec's
specs. I do not know if this is still the case. Heroichi(HEC) was another.

Since the -12V line is not used, it's not under load. Remote sensing of
output voltage does not occur and output voltage may fluctuate. I just
tested mine with Speedfan. It's at -12.16V and holding solid.