Geiger counter like clicking sounds coming from case

I don't think it is a fan...I've opened the case and have tried to pinpoint it, it seems it could be coming from the lower part where the PSU is, but I'm not sure. Also, I'm not sure if this is related...but when I started my PC i noticed at the one of the screens where is shows the mobo brand is says 3 cores activated, but I have a 955 Phenom, I seem to remember it saying 4 activated but I could be wrong, but then when I ran cpu-z it lists the name as the x3 phenom but under specfication it says x4 955 and at teh bottom is says 3 next to cores and threads.

This is my copied form my build thread...I just built this PC.

SAMSUNG Spinpoint F3 HD103SJ 1TB 7200 RPM SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive
ASUS VH236H Black 23" 2ms(GTG) HDMI Widescreen Full HD 1080P LCD Monitor
ASUS M4A89GTD PRO/USB3 AM3 AMD 890GX SATA 6Gb/s USB 3.0 HDMI ATX AMD Motherboard

XFX HD-585X-ZNFV Radeon HD 5850 1GB 256-bit DDR5 PCI Express 2.1 x16 HDCP Ready CrossFireX Support Video Card w/ Eyefinity

G.SKILL Ripjaws Series 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666) Desktop Memory Model
AMD Phenom II X4 955 Black Edition Deneb 3.2GHz Socket AM3 125W Quad-Core Processor Model HDZ955FBGMBOX
Antec Nine Hundred Two Black Steel ATX Mid Tower Computer Case
Antec EarthWatts EA750 750W Continuous Power ATX12V version 2.3 SLI Certified CrossFire Ready 80 PLUS Certified Active PFC

If your hard drive is installed down near your power supply (i.e. it's the hard drive making the clicking sound), that's a sign of it's impending failure.

-Wolf sends

My first thought was hard drive.

Could be a wire touching a fan.

Hit cntrl+alt+del and open task manager. Click the performance tab and tell us how many cpu graphs you see under cpu usage history.

There are 4 separate graphs.

Have you tried unscrewing the hdd and holding it to your ear to make sure it's not that? If it's psu, I would go ahead and return it.

If your showing 4 seperate graphs in task manager then your running 4 cores, not sure why your bios and cpu-z would only show 3 cores, that's very strange.

Have you run any kind of stress test on it to make sure all the cores are working properly? (prime95)

It's possible there's a bad core I guess. I don't know if the cpu has a built in shut down if a core is not working correctly or not.

That's why you should do some Prime95 stress testing, it will tell you if a core fails under load.