[SOLVED] Computer stuck in restarting loop.

Hi guys,

A few hours ago I plugged an Acer SD CardReader into my Computer plus a small fan but when I tried to boot my PC up it kept restarting after about two seconds before I can even try enter BIOS.
I tried unplugging everything, starting with RAM, took both RAM sticks out then plugged them back in one by one. I tried unplugging my Hard Drive, all CD/DVD Drives, mouse, keyboard, USB's... everything.
I eventually resorted to taking the CMOS battery out for a few minutes (with everything still unplugged) then put it back in, plugged the power back and put my PC on and it booted up fine so I turned it off cause I wanted to plug everything back in again but after I did that I was back at point A with a restarting computer.
I tried taking the CMOS battery out again but this time it didn't fix anything...My Computer's been working perfectly until now. I also tried removing the Acer SD CardReader + new fan but that didn't fix anything either. My Computer's about 3 years old already.

Sorry i'm quite a noob when it comes to specs...

*Intel Core i3-530 (2.93Ghz ) CPU
*1X Kingston 2G RAM
*1X Apacer 4G RAM
*2TB Seagate Hard Drive
*Onboard HD Graphics
*BIOSTAR H55 HD Motherboard
*LG SuperMulti DVD Drive
*BENQ DVD Drive
*AOpen DVD Drive
*Acer SD CardReader
*1 Cooler Master Fan
*2 Smaller Fans
*ATX12V Power Supply

Is there any way I can fix this problem? One thing which comes to mind is a while ago I changed settings around in the BIOS, when I had just two fans I changed the settings to automated fan speeds for a 'quieter' computer. Could this have anything to do with it?

Thanks.