I've was looking at PSU's but I cannot find the dimensions for this one anywhere. I have an MicroATX chassis but my current PSU is somewhere along the lines of 6.5"(l)x3.5"(h)x5.5"(w) with even a little extra space.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817152039
http://www.newegg.com/Product/Product.aspx?Item=N82E16817152039