I put together this computer about 3 months ago, installed Windows 7 and run without problems until the other day when I started it up and all I got was 3 consecutive beeps all the time, no boot screen, no BIOS screen, nothing, the dvd drives seem to work as well as the fans but thats about it so I searched the web on my laptop for this symptoms and found that I had to reset the RAM which I did, shut it off, unplug the RAM, put it back in, disconnect power cable and push star button on computer, connect power cable again and turn on computer, now, at this point there is no more beeps but still nothing!!

The computer turns on, fans, dvd drives, hard drive, but still a black screen, in fact, my screen shows the no signal sign and goes on energy saving mode, which means there is no signal going from the board to the screen, no boot, no BIOS screen, nothing? Do I have a faulty mother board? is there any test I can run to diagnose the problem? Any advice will be appreciated, thanks in advance.
Here are the specs of the pc;
- ASUS M2N68-AM PLUS Socket AM2+
- AMD Phenom X3 8450e 2.1Ghz
- Patriot 2GB PC2-6400 DDR2 RAM
- Seagate 320GB Serial ATA HD. 7200/16MB/SATA-3G
- LG 24X DVDRW SATA
- Windows 7 SP1