How could I install a new 12 volt backlight?

Okay, first of all you cannot just solder in a voltage regulator directly to your 80 volt output is just going to blow your new backlight. First things first we need to get some information about your new backlight, and your tv. Specifically what is the current rating of the light, and what is the current output of the TV power supply driver?

While hooking up a voltage regulator will change the output voltage it will not limit the current. This will be just like hooking up and led up directly to a battery. Once you have the current output and the current rating we can design a circuit that will limit the current, and drop the voltage, the circuit will most likely integrate a voltage regulator. You also probably need a couple of half watt or 1 watt resistors dropping from 80 volts down to 12 volts will cause a high rate of power dissipation, and since your television will be running for extended periods of time, you will want to make the circuit as close to indestructible as possible. Also keep in mind that the voltage regulator dropping from 80 down to 12 volts is also going to be dissipating a great deal of heat, you're going to have to have a heat sink attached to it and that will take up a bit of space, and you don't want that touching any of the plastic parts of the television.

Please post the following information:

Backlight power dissipation, and current rating.

Television monitor driver current output.

You should be able to find all this in the data sheet for the light bar, might have to do some digging to get the information about the television driver output. If you can't find the information for the television we can still probably design the circuit by assuming that the television current source will attempt to supply infinite current, it would just be nice to have that information handy.

Well, here's the problem. The backlight I purchased had literally no documentation attached. It's a cheap one from China. All I know is that the LED driver that it shipped with runs on 12 volts at least, and it needs an enable signal. I am very hesitant to attach my multimeter to read the current draw of it, as my multimeter has a 10 amp capacity and has no fuse (the milliamp setting is also unfused since the original fuse blew and I just decided to bypass it)

What I meant about tying a regulator to the 80v output, I meant attaching the new driver to that with the 12v regulator or something. The LED driver would then limit the current if I am not mistaken, since it ran just fine from the PC power supply. If I can grab power from somewhere else on the power board that turns off when it goes into sleep mode, then that would be great. The enable line on the LED driver can take as little as 5v (based on what I used on the PC power supply) to turn on, so that can be separate.

As for the calibration and whatnot, I don't really think that's necessary, because I ran the panel with the new backlight in there and I was very satisfied with the results. It works, but now I'm just looking for a way to run it as just the monitor, not a string of parts everywhere.

I will do some research on the monitor. It is an ASUS VK248. What I do know is that the power going to the logic is just 5v.

In my opinion, there appears to be plenty of space for a heat sink to fit within the metal shielding of the device. Here's some pictures to maybe give you guys a better idea. https://drive.google.com/folderview?id=0B5FOtrrp9MnYZDMwcHI1TUJxOUU&usp=sharing

That LED bar isn't  going to be pulling anything close to 10 amps. My stove in my kitchen doesn't pull 10 amps. You should be fine to use your meter.

That LED bar isn't  going to be pulling anything close to 10 amps. My stove in my kitchen doesn't pull 10 amps. You should be fine to use your meter.