Overshoot Transient testing query

[crmaris]

Hello again! I have a question about the transient Overshooting tests of XFX XPS 650W

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story2&reid=181

You say"5VSB only spiked up to just over 3 volts, and the 12V rail barely hit eight volts." So the ATX specification approves every spike that is between 0-5(+10%)Volts and 0-12(+10%)Volts and rejects any negative values, right?

Also in Thermaltake Toughpower XT 775W review, unlike the XFX review, the transient graphs do not return to zero but stabilize at the rated volts (5V and 12V). Can you please tell me what changed? I am trying to do the same thing with my stingray and a generic 300W psu but I can only get graphs like the XFX review (the spikes return to zero).

[Oklahoma Wolf]

So the ATX specification approves every spike that is between 0-5(+10%)Volts and 0-12(+10%)Volts and rejects any negative values, right?

Right.

Also in Thermaltake Toughpower XT 775W review, unlike the XFX review, the transient graphs do not return to zero but stabilize at the rated volts (5V and 12V). Can you please tell me what changed? I am trying to do the same thing with my stingray and a generic 300W psu but I can only get graphs like the XFX review (the spikes return to zero).

Set the scope to DC instead of AC.

[crmaris]

Thanks very much!!