Thanks everybody for replying... This power supply is Japanese brand PSU and now im studying in japan.. It has 13.5cm fan and from what ive read from reviews,they said this PSU was really quiet and has all the neccessary cables..Its price also affordable for 400W,about 5000yen..Antec and Enermax PSU were quite pricey here in japan.. This is the link for this product.. http://www.scythe.co.jp/power/gouriki.html And the link of homepage.. http://www.scythe.co.jp/ Both are japanese lang so to change lang,please select the flag on top right of the homepage.. But from what Ive looked,this PSU only shown on the japanese vers website...So this is Google translated Eng vers.. http://translate.google.com/translate?u=ht...Flanguage_tools So how much watt should i need to power up my system..??