Is there a piece of software (hopefully freeware too!) that can calculate
the system's current power usage in watts, etc? I know some programs tell
you what the current voltages are, etc, but I'm more after a power usage
monitor that can show you if your system is on the cusp of draining more
power than the power supply is built for.
Thanks.
There's no way to come close to an accurate reading with just
software, would be more of a guess.
With a moderate loading on the power supply the rails should
stabilize, and you'll have a baseline reading. As the power supply
load increases beyond it's capacity, the voltage on the overloaded
rail will drop. At that point the power supply tried to compensate,
and to keep that inadequate rail voltage high, it will raise the other
voltage rails. So the symptom whould be a signficant deviation from
moderate load, EITHER too high or too low. This is ignoring a lot of
things, assuming at least a power supply of somewhat fair quality.
However, the voltage readings cannot come from the motherboard.
Motherboard voltage readings can only accurately indicate the voltage
level at that exact point in the circuit at which the reading is
taken, which might be near enough to actual power supply output, but
is often below that. Use of a voltage meter on the power supply leads
is necessary to take a more accurate reading.
If your 400W PSU is quality name-brand unit, the odds are you won't be
able to overload it very easily, not with CPU, memory, video card or
drive upgrades, unless you had a special circumstance like dual CPU,
multiple high-end video cards, peltier or a dozen hard drives.
On the other hand, if the power supply is generic it may not even be
worth 300W output regardless of a 400W label, but many high-end
systems don't even draw 300W unless heavily loaded, the larger issue
may be the safety and ripple, recovery time, longevity.
Dave
