A Detailed Look
The Zalman ZM1000-HP 1,000W power supply features a dark gray chrome electroplate finish (Titanium) that is very attractive but easily scratched. The enclosure is 210mm (8.25”) deep and uses a single 140mm fan on the bottom for cooling. The power receptacle and LED indicator below it are the only two features on the backside panel. The indicator light is red in standby mode when power is applied but the PSU is turned off. It lights green when the PSU is turned on and operating normally.
The fan speed is automatically controlled by the internal component temperature (speeds up as the combined load and temperature increases). The Zalman labeled fan (ZF1425ATF) incorporates dual ball bearings and is rated for 0.26A at 12V.
The open honey comb grill on the back and slot openings across the front allows air to exhaust out of the power supply for cooling all the internal components.
One of the ZM1000-HP’s more unique features is what Zalman calls the “Standby Noise Suppressor”. It is controlled by a small rocker switch on the front side of the power supply (inside your PC). According to the User’s Manual “The 5Vsb Noise Filter eliminates high frequency noise in standby mode”. OK, what’s the catch? Why not leave it On all the time? Why even have a switch?
Edit 3-3-08: The good folks at Zalman responded to my questions and here is what they had to say: The Stby Noise Filter Switch eliminates the high pitched noise that sometimes is generated from the PSU. The reason for the on/off switch is because the noise filter consumes extra power in standby mode (when the computer is turned off but still plugged into the AC mains). To be ROHS certified, the stby power consumption has to be less than 1W but with the noise filter on, it exceeds 1W.
OK, there you have it. If you are particularly sensitive to high pitched noises and you find the ZM1000-HP generates such a noise, then turn on the noise filter switch. However, the majority of users can just leave it turned off and save a little electricity.