Yesterday I went to a LAN party with my rig and for some unknown reason it wouldn't boot up. Just wouldn't. The monitor would show "no signal" sign when system was powered on.

Weird thing, when IDE cables from hard drives and CD-Drives were UNPLUGGED from motherboard, I could actually see hard drives and CD-Drives working, as in opening and vibrating. But when I plugged the IDE cables back into the motherboard, both the CD-Drives and hard drives didn't make a single noise or vibrate so I presume they were not working.

CPU fan is on. I tried 2nd video card and same result. Took out memory. Same. Unplugged everything but video card = same.

I'm thinking it's mobo?

But why would it die though? I woke up in morning, turned on the pc as usual and then 2 hours later I turned it off, unplugged and drove to my friends house where it broke...

I tried everything.

From clearing CMOS to taking the system apart to swapping video cards.

Same result, black screen, no sounds. One of the DVD-Drives doesn't work when plugged into the mobo. When unplugged from the mobo, both of my CD-Drives funciton properly.

Hard drives don't spin when plugged into the mobo, yet do spin up and vibrate once unplugged.

I'll try another PSU tomorrow.

I do not think its a PSU because it works properly, the PSU fan spins up and lights up, all the case fans work...

Could it be the CPU?

Then if it was CPU why wouldn't the drives work?

I tried removing both sticks of RAM and then inserting one and booting up, and then another, same result, black screen, no signal.

I will try a 3rd stick of ram from my sis PC, see if that will do anything.

What else could it be? PSU, CPU, Mobo? Could it be that CMOS battery ran out of juice. ?

Any help would be greatly appreciated. Thank you.

Your graphics card seems to be out of order ... do you have a built in card or an external one ? If external, try replacing it with some other trusted one.

Tried that already. Like first thing I did. Nothing. Same result. Doesn't boot up. Drives don't work when connected to mobo. All fans spinning.

I have the same proble....untill now no cure...guess have to send to repair by specialist...i have done all the troubleshooting as u did....even replace cmos battery...same! dead!

Similar thing happened to me (regarding the hard-drive and CD-ROM) when I (stupid me) plugged the IDE cable upside-down. Luckly for me, I didn't do any damage. My machine was acting dead just like yours ('till I plugged it right again).
Yet, you say you drove it in your car. Well, the vibrations could've benefted to the damage. My advice would be to ispect your mobo for any cracks in the solders, starting with your VGA slot.
I know, it's a long shot, but you never know...