The problem is that there isn't any review of the VP450 that would let us fully judge its electrical performance. The old review at Hardware Secrets doesn't measure in detail many important factors.
To see how well a PSU performs, we should at least see:
a) voltage deviation across the whole load range, and not just the highest value - we have to know at which point the voltage was furthest away from the nominal value; whether it happens at low load or high load and what kind of deviation can we expect at the usual load levels.
You should be able to calculate it from the tables, or see on the graphs like this (simple example):
b) voltage drop across the load range - measures how far the voltage dropped from low load to full load. Diodes and MOSFETs on motherboards and graphics cards can stand being fed 12.5V or 11.70V constantly, as long as it's in spec. But when they are getting 12.4V one second, then suddenly 11.65V for a moment, then again 12.3V or so as the power consumption in the system changes, they wear quicker.
You can output 12.4V at 10% load and 11.7V at 100% load - that's fine and in spec, but as you jump from low loads to high loads, the voltage change is significant.
If you were outputting the same 12.4V at 10% load and 12.3V at 100% load, then the worst-case voltage deviation is the same (3.3%), but the voltage drop across the load range is far smaller.
Here's how it can look:
They both stayed within ~2% of their nominal values, but the right one could hold its value much tighter.
c) ripple - how much ripple and noise is there at the outputs at different load levels, both high-frequency and low-frequency.
d) If the website has the right tools, they may also measure transient load reaction - how much the voltages drop when you hit them with very brief loads. Good results are a combination of voltage deviation and voltage drop, because the values cannot drop below the ATX specifications, and it's also preferable when the total drop is as little as possible.
HardOCP tests transient response, as does crmaris.
For example: you're outputting 12.20V on the +12V rail, and you hit it with a transient load. It dropped to 11.72V. The drop is 0.5V, but it didn't drop outside of the ATX spec.
On another PSU, you're getting 11.70V. When hit with a transient load, it drops to 11.39V. The drop is lesser than the first unit, but it dropped out of ATX tolerance range.
e) Another thing that reviewers are usually able to measure is hold-up time, which measures how long the PSU can keep the voltages in spec when the power is cut. Say, you live in a neighbourhood with frequent brown-outs - a PSU with good hold-up time will work fine when the input AC isn't fine for 13ms, but a worse PSU will just shut off. You lost your unsaved work, documents, and some hard drives can be hurt too.
In the
VP450 review, we can only see the following:
a) ripple and noise (for all load levels) - it reaches 75-80mV, which isn't low.
b) voltage deviation - only that it never exceeded 3%, the actual values across the loads are unknown,
c) exhaust temp, efficiency, power factor - not directly related to the power your components get.
We don't know one of the most important things - how the voltages changed over time, so we have no way of knowing at which point did the voltages deviated furthest from the nominal value, and also how much they dropped over the full range. Reading that they never deviated further than 3% is not enough, because that leaves a lot of different possibilities:
We don't know hold-up time, crossload, or transient response either.
So from the important things we only know ripple, which is high - and also that voltages don't deviate further than 3% at any point. The other most important characteristics are unknown, so that's a shame.
Good marks for efficiency, ability to output full power and working OCP are nice points, but the most important things you look at in a power supply are voltage behaviour and ripple suppression.
There's also the build quality side to this, but you can all read that - the fan is sleeve bearing, and the secondary capacitors are Capxon KF and Teapo.
So, I wish Gabriel Torres had included more detailed results in this review, rather than only ripple analysis and single-digit voltage regulation comment, because we simply don't know how good this PSU is - and if we only go by ripple (from the performance measurements), it's over the half of the ATX limit.
He later started including load/voltage tables in his reviews, so that's nice.
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