My computer powers on but doesn't boot to BIOS or Windows. Motherboard light comes up after powering the system on and all the fans also run fine. Its just that HDD light doesn't come up at all and the power light on monitor blinks constantly. I have already tried swappng the RAM to different slot which too didn't work. When I took off the RAM and powered the system on , it started giving Beep sound which makes sense that MB is OK at this time. Please advise.