Nothing is running right, could my psu or hdd be failing?

My specs :

Ram : 2 gbs of corsair ddr2 800, 4-4-4-12
Video : evga 8800 gts 320mb the fastest model of the 8800 gts series.
Processor : e6400
PSU : 500 watt Antec/smart power
Hard drive : 500 gb maxtor


My problem :

Someone said if my harddrive is making loud noises to start there. But, it makes a small clicking sound. Like when I load a web page or extract a rar file, or playing a game. But, as far as I can remember about 5-7 months ago, It seem this drive always kinda made a little noise.

When I had vista on my machine, and If it went IDLE, I would have to turn the pc off and turn the PSU off manually. Then I would have to wait 30 seconds, flip it back on and it'll. I'm wondering if my video card isn't getting enough power fully.

When I play crysis, or CSS. People look laggy. People teleport everywhere, it drives me crazy. The strange thing is that it's all of the servers not just 1. When I spec people, you would think they hacked how shaky they were. Everything is shaky, the people that run next to twitch, my bullets don't register. I'm hitting 100-250 fps, so It can't be my video card.

What would be the best solution? I know my cable modem is dying. I was gonna go trade it in for another one. So far, I think it either could be my hdd,CM or the PSU.


What do you think it could be?

 

Thanks man, I don't know if it's a clicking noise. It's a sound I can't describe.