Try to clear the CMOS removing the CMOS battery and all power cables from the power supply to the motherboard, leaving the system without power for 20 minutes at least after that move the BIOS jumper from pins 1 and 2 to pins 2 and 3, then power up the motherboard. if you get display, the system would boot directly to the BIOS maintenance tab, if so, load defaults using F9 and then save the changes and exit the BIOS with F10. Once this is done, tunr off the motherboard and then move the BIOS jumper to pins 1 and 2 as normal, and test again.
If the problem persists, try a recovery but using an USB thumb drive, just be sure to remove any other media not required for the recovery, like hard drives, DVD/CD ROM drives, card readers, USB printers or other devices connected, even remove the mouse and keyboard, just have the system with the motherboard, processor, Heat Sink and fan, power supply, one memory stick and the USB thumb drive with the .bio file for the recovery. You may see no video display at all for about 15 minutes, so just let it go for about that time, if it works the video should come up saying that the BIOS is being flashed.
i followed ypu rintructions and what happens is that the system shuts down after 3 mins. when i turn it on, i here a few bips and then (1-2 mins later) it shuts down again. is the motherboard destroied?
Check how many beeps do you get and compare them to the following site
Check the rest of components installed on the system and make sure that they are compatible