My Mac won't connect to display. (Mini DVI to VGA))

I am very experienced with my mac, I have had mac for 8 years and I'm a "computer whiz". A month or two ago I got a Mini DVI to VGA adapter and it worked great on every display until last week, it just stopped connecting to my displays. I figured it was the adapter but after I bought a new one (and a new vga cable) and tried it on ALL 3 of my flat screens in my house. I decided, it is an internal hardware or software issue. Yes, I have mirroring turned on before you ask. I have defaulted all settings and nothing worked. I hope it is a software issue that I could fix (I am awesome with software issues) but if it is hardware or motherboard related... then bob freaking saget.

Layout:
Mac OS X 10.5.8
VGA Cable (x3)
Mini DVI to VGA Adapter (x2)
TV (x3)

I appreciate any help!

You wouldn't happen to have someone with a Mini to DVI would you? I ran into this once with a Mini to VGA and thought it was the adapter or the monitor as well. After changing all settings on the monitor and couldn't get it to recognize, I swapped the VGA for a DVI that was laying around and it worked fine, thus ruling out internal issues. I would try this first if you have access to a DVI before narrowing it down to motherboard.

@Steven_James I was thinking about that, but with HDMI but I didn't know if it was the port itself that was broke. Thankyou, you have been the most help out of anybody, including Apple Customer Support (facepalm.)

Sorry, it amazes me at how many people post topics on here, and they have high volumes of people looking at them, but hardly ever suggestions. I would at least start with another adapter, not necessarily another VGA. It seems to be an internal issue, at least you have 3 different devices to test on so we know it isn't the other units (displays) that have issues. It helps out tremendously when you have various equipment to test with.