HELP!!!! No Display

Ok people I've got a BIG problem and I'd appreciate if someone here could help me.
Last night while I was trying to replace a hard disk with a DVD drive and after a dosen hard reboots I tried to turn on my PC to see that there's no display.
My monitor was giving me "No Signal" and no matter how many times I checked the connection there wasn't a sign of life.
I removed every unnecessary devise such as hard drives and CD Roms but nothing changed.
I thought that maybe there was some problem with my monitor so I moved my PC to the living room and connected it to the LCD with a S-Video cable.
Unfortunately there were no life signals either.
Finally I removed the CMOS battery for a few minutes and after putting it back the computer booted.
However after a restart it becomes "dead" again and I have to remove the CMOS battery to make it work again.
I connected a DVD drive and booted a LiveCD I had to ask for help.
My guess is that there's something wrong with the graphics card or the motherboard.
Any ideas?

I don't want to insult you and I assume that you did that, but: When checking connections did you also try removing the video card and insert it again? Just a(n amateurish) shot in the dark, and admittedly it doesn't fit with the battery phenomenon.

Originally Posted by lghartveit
When checking connections did you also try removing the video card and insert it again?

I did.

(10 character limit)

Does the motherboard include integrated graphics?

Is the power cable connected to the graphicscard (if it requires it)?

Originally Posted by hishadow
Does the motherboard include integrated graphics?

I think it does but it needs a female cable and I only have a male one.

Have you checked the DVI/VGA cable-end for broken pins?

I would but since the problem still exists with the S-Video cable I think there's no reason.I'm quite sure the problem is interior.

Originally Posted by Kostaz
I think it does but it needs a female cable and I only have a male one.

Does your motherboard have VGA or DVI out like one of these? Or else it might be video out for an adapter like for dual-screen etc.

Also, did you check that the graphicscard needed a powercable.

Originally Posted by hishadow
Does your motherboard have VGA or DVI out like one of these? Or else it might be video out for an adapter like for dual-screen etc.

Also, did you check that the graphicscard needed a powercable.

My motherboard has 2 male VGA plugs.
I checked the powercable even replaced it but no difference.

Originally Posted by Kostaz
My motherboard has 2 male VGA plugs.
I checked the powercable even replaced it but no difference.

I bet those are COM ports and not VGA. Anyway, ignore that issue and see if you can borrow a new graphicscard.

You could also try removing your graphicscard and boot your computer without it installed, then try with it reinstalled.

Originally Posted by hishadow
I bet those are COM ports and not VGA.

Probably

Anyway, ignore that issue and see if you can borrow a new graphicscard.

Just great right now every one of my friends is on vacation.

You could also try removing your graphicscard and boot your computer without it installed, then try with it reinstalled.

Where am I going to connect the monitor if there's no graphics card?

No mainboard that I've ever seen will boot without a graphics card anyways, unless it has an integrated graphics chip.

Many server mobos do, but it's unlikely that we're dealing with one here.

Do you get picture after resetting the Bios?

Yes, clear the CMOS and if you get a picture boot with failsafe defaults.

Make sure all your memory modules are properly seated. If they're not all the way inserted, you may lose your display.

Real basic question.

Was the harddrive you replaced the boot harddrive?

Originally Posted by woges
Do you get picture after resetting the Bios?

Yes but after rebooting the picture was lost.

Originally Posted by Gorath
Yes, clear the CMOS and if you get a picture boot with failsafe defaults.

If I change anything in bios including the default setting I don' t get picture.

Originally Posted by Squeek
Make sure all your memory modules are properly seated. If they're not all the way inserted, you may lose your display.

They're all properly seated.

Originally Posted by Thrasher
Real basic question.

Was the harddrive you replaced the boot harddrive?

It's a really long story but the answer is yes.

Ah, so needeed to reinstall the OS? OR…?

I borrowed a graphics card and a CMOS battery from a friend but there wasn't any improvement.
Actually the problem is in one of the motherboard's memory slots (thanks for the hint Squeek) and once I freed that slot everything was back to normal.Fortunately I just moved the memory to another slot and I'll avoid placing anything in the faulty one in the future.

Big thanks to :
lghartveit
hishadow
JDR13
Prime Junta
woges
Gorath
Squeek
Thrasher
For trying to help,I appreciate it guys.

Case closed.

Originally Posted by Thrasher
Ah, so needeed to reinstall the OS? OR…?

I wanted to replace a hard drive with a DVD Rom.