I bought a Zalman Z9 PLus case yesterda and installed everything. It was all well until this evening where i heard this increasing sound ( of a fan?) and then decreasing sound). At first i believed it to be my case fan controller not working or my CPU fan...but this was not the case. I eventually found that it was my PSU making a fair bit of noise that it never had before! Over the last half hour it has got louder then quieter. Could this be due to me placing the PSU fan face down on the bottom of the case? Should i turn it over? I never experienced this much noise with my previous case (that had the PSU mounted at the top).