Desktop won't connect to tv

[DarkWolfD]

I recently got a dell inspirion desktop and am trying to connect it to my tv, which is a 17 inch by 10.5 inch (just counting the black screen) Insignia. I'm using an hdmi cable and I am on the hdmi input on the tv. I'm not sure if my tv is hd or not. My tv also has a port labeled "vga in" but the vga cable doesn't seem to fit with it, and my computer also has a vga port. I tried both the hdmi an so vga cables but every time it said "no signal" on the tv. What is going wrong?

 

[Herc08]

Do you have a GPU in your desktop? Does it work with a regular monitor? Is there more than one HDMI input on your TV?

 

[Animus3D]

As copied from the "How to Ask for Troubleshooting" guide:
When was the last time the computer worked right?
Was there something that happened right before things got bad?
Did you install some hardware?
Did you install some software?

-----

Are you able to access the BIOS?
Have you tried resetting the CMOS?
Also what do you mean "the vga cable doesnt seem to fit with [the vga port]"?