Right now I am using Intex 450W power supply. I have connected one usb wireless adaptor of netgear and also connected usb speakers of logitech. Sometimes, I also use USB portable HDD seagate freeagent. and I have also connected two internel HDD one is of seagate and other is of WD hd. But problem is that weird noise is coming from computer. I think its due to powersupply bcoz I already replaced heatsink and cpufan and also cleaned the dust. I want know, should I use 550 Watt instead of 450 Watt bcoz may be, i am using so much usb devices. So, its not able to give accurate power to all components. So, tell me should i use more watts of power supply.