PC to HDTV using VGA Cable

Hi Guys

First off....apologies if this is something that has already been covered. Its just that I've spent some time digging around and have not been able to find the solution to my issue.

The Issue -
I have a Samsung 50" Plasma TV that I bought in 2007. I also have a Compaq Laptop and a Desktop PC. My PC is permanently connected to my TV using an HDMI Cable. If i recall correctly, i have a Nvidia Geforce 7600 GS video card attached to the motherboard that has the HD output.

I just got myself a VGA (male to male) cable to try and connect the PC to the tv using VGA instead of HDMI (dont ask why, different reasons).
Now the problem that I'm facing is that when the VGA cable is plugged into the TV and the PC, the TV DOES recognise a PC connection, but switches itself onto standby mode within 3 secs.
I updated the graphics card's drivers to the most recent (may 09) and have played around with the options. The one thing I noticed is that the nvidia control panel has a section called "Change the Signal or HD format" which only has one option - HDMI. Not quite sure if its supposed to have more or like a VGA option or something.

Now to rule out whether the TV or the VGA cable have problems, I connected the cable to the laptop and TV and it worked just fine. Its only when i connect the PC that the TV goes on standby within 3 secs and i get no output in PC mode at all.

One other fact that I noticed is that the laptop,s graphic card had those simple output options, like the one that say output to monitor + notebook etc. I dont have the same format or options with the PC. I'm assuming the reason behind this is cause the laptop's graphics are inbuilt onto the motherboard whereas the PC graphics card is different from Motherboard.

Is there any way I can use the graphic output from PC motherboard (which i assume will be the solution here but NOT using the HD output from attached card) and thereby get the damn thing to start working using the vGA connection?

I would appreciate any help that you can give me with this problem.


Thanks
ks

PS: I've tried the solution of earthing the 10th pin on the vga cable, the pc options hows up, but in my case that is not the problem as i have the pc option showing up anyways...its just that there is no output thru the VGA stream.