Will quickly explain my problem. Looks like a dead machine to me... Please help, in case any of you know the answer to this.

PC Config:
Intel Core 2 Duo processor on a Intel DG065RY motherboard, 2 DVD ROM's, XFX Force GeForce 7600 GS, 2 x 1 GB 800 FSB RAM & 2 x 1 GB 533 FSB RAM. (Total 4 Gigs). LG DVD Writer + 1 Sony DVD Combo. Chieftec 350 Watts Power Supply to support the same.

Sympotms / Behavior:
1. One fine morning, I saw my PC in a frozen state
2. I restarted my machine, and saw that only the Power LED and the LG DVD Writer illuminate. My other DVD ROM, Hard Disk LED don't illuminate.
3. When I followed some steps on the Intel site (mobo troubleshooting), and after keeping my PC powered off for around 6+ hours, I tried restarting and it rebooted properly.
4. The next time, I shut it down, and rebooted again, the same thing happened. It refused to boot.
5. As of now, it illuminates the Hard Disk LED, illuminates both my ROM's, but not the Power LED.

HELP... Does anyone know, what is wrong? :-(

PS.: I had re-installed all the components. i.e. One by one, I went on adding components. I hear no noises (short or anything) during booting. Does absence of a branded Thermal Grease cause such problems?

fist think i would do is test the power supply,,or try a new power supply .

fist think i would do is test the power supply,,or try a new power supply .

Yup. I did that. Found out a problem too. I don't get memory beeps when I remove the RAM modules from my motherboard. Ideally it should give me long beeps eh? It does not happen though. I have contacted Intel Support for this. They have asked me to do a couple of things too. Might be up for a replacement...

Thanks for your reply :-)