In November last year I wrote a guest article on PCMech.com called “Why Your Power Supply Choice is so Important”. With today’s power-hungry top-spec gaming rigs, a lot of them custom-built by supergeek-gamers/power-users (In more than one sense of the phrase.), probably using Intel Core i7 Extreme processors, and multiple juice-guzzling nVidia and/or ATI graphics-cards; the requirement to have a top-class, noiseless, and reliable PSU which is able to deliver all the massive power needs on demand is paramount.

Fortunately there are a number of them around; and the Zalman ZM1000-HP 1000W Power Supply is one of the best of them.

This video is fairly self-explanatory; which not only aids the presentation, but also saves me a bit of typing. There’s just one point that the narrator makes in the early part of the video, though, that I have issues with: -

He says:

“…To understand that you need to know what rails are: Rails are basically well-regulated transformers which convert domestic voltages into voltages which your computer system can use…”

Bzzzzzzzzzzt! With due respect to the author; no: That’s not correct: -

Rails are the final voltage output lines – from those well regulated transformer[/rectifier] units[/circuits] that convert [the domestic supply from AC to DC current at] voltages[/wattages] that your computer system can use.

What I’m saying here is that (power) rails aren’t the power supply unit itself; any more than train-track rails are the railway station. The electricity flows from the regulated transformer/power units along the power rails, in the same way as a train runs along a train-track after coming out of the railway-station.

This may appear to some to be just a minor issue; but I thought it prudent to correct that terminology-error before proceeding further.

…And another point that I’ve only just noticed on April 2nd is that he talks about a combined power of 80 Amps

Bzzzzzzt! : Incorrect use of terminology: Electrical power is measured in Watts; not Amps. He should have said a combined currentof 80 amps. – Amps being a measurement of electrical current: So; just to be ultra-pedantic; that means that the total power output available from all +12 volt rails is 80 amps X 12 volts = 960 watts Max: That’s quite something! However; having said that, since the whole unit is rated at 1000 watts; that won’t leave a lot on the 3.3 and 5 volt rails: Only 40 watts remains; which at 3.3 volts leaves only 12.123 amps available for the CPU without consideration of the 5 volt rail.

Therefore; whilst the +12 volt rails are designed to be loaded to a maximum of 80 amps without damage ocurring; the actual available load will be somewhat less than that with respect to the loading on the 5 and 3.3 volt lines.
If the processor (and motherboard, combined) were using 65 watts of power that would be 19.7 amps accounted for at 3.3 volts. (For the sake of simplicity and clarity I’m ignoring the 5 volt supply in these calculations.) If we were to relate that loss to the 12v lines thus: –

12v / 3.3v = 3.64 ¬ 19.7/3.64 = 5.4121 amps away from the previous figure of 80 amps leaves 74.5879 amps; which translates into 74.5879 X 12 = a fraction over 895 watts in total available on the 12 volt rails. – That’s still one heck of a shedload of power; but not as much as the narrator makes it out to be.

Having cleared up that little matter; on with the video: -

- So if you’re building a top-spec gaming-box; forget buying cheap: This PSU isn’t – BUT it’s an excellent buy, and, as you may see, it does its job very well.