No signal to screen and keyboard gets no power?

Hello.
One day, when i started my computer up.
Suddenly, it freezed.
Then I just restarted it, on the power button.
And after that, I didnt get any signal at all to the screen. It just says " No signal " .
I have tryed the screen on other computer, and it works all fine.
The keyboard, dont turn on either anymore, it dosent work on my computer, but fine on others.
What can this be, anyone can help me?
Im not very good at computers, but I know several things, so im not completely lost.
I will be very happy, for any response and help.
 
Some info about my pc

Motherboard
IPIBL-LB (Benicia)
Processor
Core 2 Quad Q6600
Memory
4 GB
Video graphics
NVIDIA GeForce 9600 GS
Integrated graphics using Intel GMA 3100
Hard drive
1 TB (2 x 500 GB)
Computer Case
Mid-size ATX
Power Supply
300W
 
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