Computer wont switch on !!!

My computer is not switching on. The motherboard is recieving power because the lights on the motherboard are working fine and are switched on when the power is connected to the computer but when i try to turn on the computer it just doesnt do anything. If however i unplug the power cable and plug it back again and then try to turn on my computer then the red light of the CPU flashes for one second but the computer still doesnt turn on after that when i press the button again it just doesnt do anything ... Any help guys ?

you should hear audible beeps. If you do (and you should) that is a bios indicator of what the problem is. It's most likely a hardware related problem. If you hear beeps, post the beep sequence such as 3 short, 3 long, 3 short (which btw is also morse code for SOS) and if you know it the bios manufacturer. If you don't know the bios manufacturer, try to enter setup when the computer tries to boot and it should be listed, for example AMIBIOS.

Check your RAM. I think your RAM is damaged and needs to be replace.

If the main cpu/power light flashes on but then immediately of.
after reset of the power supply(you unplug it and plug it back in)
I would say there is a short somewhere or there is something wrong with your power supply.

I recomend checking every thing inside your computer for
a crossed wire
burnt spot on the board
metal object on the board that does not belong(Ex.a screw)
cpu damage
ram damage
chipset damage

you get the idea

So i tried everything and then i took it to a shop for repair. Turns out my PCI-Express card is not working. He replaced the PCI-E card with another one of his own and bam, computer started working .. I still cant understand why it wont even turn on though. I mean if the problem is because of the Graphics Card then it should not be giving output on the monitor, it should still turn on though ?
Anyway i have to buy a new PCI-e card now. Im not a PC gamer i play my games on consoles so can you guys recommend me a good PCI-e card keeping in mind that i hardly play games on PC.

I've had this problem a few tims (no beeps)

One time the RAM needed to be reseated.

One time the power supply needed replacing.