test my psu how?

[Mizugori]

okay i have an antec truepower 430 watt. what are a few good programs to really test it; im concerned because i suspect that the voltage is varying... when i run cpu-z the core voltage will jump between 1.728 - 1.744 - 1.760 etc.

and right now the system is not even stressed afaik, i don't have it highly OCed or anything at the moment.

thanks!

 

[Ice Czar]

not the supply's job (not that it doesnt impact that)
the mobos voltage regulation modual is responsible for that voltage
taking either the +5V or +12V PSU rail and generates the high current low voltage the RAM and CPU employs

how stable the PSU supplies the VRMs however can be a contributing factor to how stable they can supply that voltage, how hot they get can also factor in, The VRMs on my K8W are some of the hottest components on the board and have impressive heatsinks

for software to observe the PSUs rails, (and the V core) you can either do that in the BIOS
or use MBM (Motherboard monitor) speedfan, ect they all take their readings from the same place the SMBus (system management bus) however that is only good to observe or log fluctuations not definative values, for those you need to take direct readings with a Multimeter

> http://www.hardwaresecrets.com/faqpowersupply.html

the stability of your supply's rails is a result of a number of factors
first the transient response it was designed with (how quickly it reacts to an altering load)
tied to the load regulation, spec is 5% , some supplies are far better than spec, next the AC source power greatly influences the ability of the supply to convert the power to DC, the spec the supply has for that are its operating range 90 to 264 VAC at 40 to 63Hz for instance, and a line regulation of some percentage say 1%

meaning its rated to produce its rated load regulation, with source power anywhere in that range (as a note thats a real good range in the example) howver if the source power falls outside that range it should shutdown, though some just flub the load regulation possibly allowing an overshoot or undershoot through to the board before blowing up
an overshoot or undershoot are where voltage outside of the 5% above are fed to the components including the VRM

other factors that can contribute to the supply being unable to maintain a stable voltage within the 5% range are sort of related, basically an overloaded rail (+3.3V, +5V or likely the +12V rail(s), since PSUs are rated at an artificially low temperature, one much lower than your likely operating temperature, the rated capacity and amps per rail arent an accurate figure, most PSU engineering specs will state something like
rated for full power at 25C decreasing to no power at 70C, so by either trying to power too high a load or allowing the supply to get too hot can effect its ability to supply voltage within the 5% range

 

[Ronbo]

CPUz shows the same kind of fluctuation on the Vcore of my Abit NF-7s ver2.0, it's a common problem, there is a pencil mod to fix this, someday I will actually get around to trying it It's not a really big problem, and hasn't affected my OC at all that I can tell (I'm prime stable for 24/7 at 12 x 210.5 at 1.85 v set in bios, 1.75 approximately in CPUz, MBM5, etc) I do notice it drops about .025-.05 volts under full load, the pencil mod should fix that also. Now where did I hide that #2 ticonderoga?