I would like to bring the spotlight to various issues regarding this product and some of it's siblings (zm850-hp for instance). It suffers from a quite extreme variant of coil whining / squealing. Some sort of electrical high pitch noise that just drives you insane. I found a good video of it here:
http://www.youtube.com/watch?v=mQa79pWC0OQ
This seems to happen with a lot of the newer graphics cards, especially Geforce 260/280/285/295 and Radeon 4850/4870X2 etc etc. It also produces the same noise when you scroll a web page or copy a file to your hard drive. In fact, any hard drive activity triggers the same sound, albeit at a lower intensity, but still very audible.
When I first got this power supply and noticed this I tried to get in contact with Zalmans support. They kept telling me that they had forwarded my messages to their supervisors who, during a period of 4 months, haven't e-mailed me back. Not even once. Even though i sent follow-up e-mails twice a week. Or they would tell me to send e-mails to this other set of addresses (support1,2,3@zalman.co.kr), which never replied either. I did this 2 times a week for 4 months.
In other words, I was being completely ignored by their so called "support". They have been indefinitely postponing any type of resolution for this problem.
The issue gets worse when you realize that even if you RMA this product, since its a manufacturing fault; you would just end up with the exact same problem.
My honest recommendation to anyone thinking about buying this power supply would be to stay away. Or do very, very thorough research on if the rest of your PC components are compatible with this PSU in such a way that it doesn't generate squealing.
