This program "killed" my Graphic Card ?

Im sorry for your situation but the program didnt kill your card, you did by running a program you didnt fully understand.
Just because its recomended dosent mean to say you should. A Bios is something that should be left well alone unless you know what you are doing and changing it either addresses a specific problem you have or its needed for compatability with something you need to run.

Now are we talking about the PC's bios or the Bios for the Graphics Card ?
Things you can try are. If we are talking about the main PC Bios going to the support page for the company that makes your motherboard and downloading the latest suported Bios and using the utility they recomend replace your existing one.
Or if its the Graphics card you would need to do the same but obviously for the GPU's company etc.

Mactronix

The thing is that, I didn't even downloaded a bios .rom file, neither clicked on the option to update it. I've just opened the program to see my BIOS version and when it was launching that my PC freezed.

And, I was trying to see my Motherboard BIOS version. Nothing to do with GPUs BIOS. That's why its weird. I did not flash anything and GPU is dead now. HOW?

See, this is the program load splash screen: (Where my PC freezed)

And this is the main screen of the program, I didn't even get here.

I've tried to reset my CMOS BIOS. And then flash with the new updated one 3/2009. But same problem is ocurring. Everything works fine when the GPU is not plugged.

Perhaps the program had nothing to do with it, and was it just a coincidence ?
I don't know what to do now. Try to flash GPU BIOS ? But I didnt even "touched it"

EDIT: More weird was the answer that BiosAgent support emailed me:

The program was at its splash screen yet. And it would access the Motherboard BIOS, not the GPU.

Anyway, I could try to reflash GPU Bios, since its the only option I have now.

My PC can only boot up with the GPU pluggend, and LCD connected to onboard GPU, until before Windows starting screen appears. After that, it freezes.
So how can I flash GPU Bios? Tell me that it's not only through Windows, please?

You didn't understand. I can only boot until the windows startup screen, when I set on BIOS to use the onboard GPU, and have the LCD plugged into it, but with the X800 plugged in PCI-E.
But when I set the BIOS to use the PCI-E as GPU, I can't even boot DOS, I got "no signal error" and no POST Screen. Only a flashing power led.

Well I found this site describing hot to flash GPU BIOS. And found out that I can flash through DOS too.

I will use ATIFlash 3.60.
And I found many different BIOS files for my Sapphire X800GTO 256/256.

Here is a list:
Sapphire X800 GTO 256 MB BIOS - Samsumg 2.0
Sapphire X800 GTO 256 MB BIOS - Samsumg 1.6
Sapphire X800 GTO 256 MB BIOS - Samsumg
Sapphire X800 GTO 256 MB BIOS
Sapphire X800 GTO Fireblade 256 MB BIOS - Samsumg 1.6
Sapphire X800 GTO² 256 MB BIOS
Sapphire X800 GTO² 256 MB BIOS - Samsumg 2.0
Sapphire X800 GTO² 256 MB BIOS - Samsumg 1.6
Sapphire X800 GTO² 256 MB BIOS

Which one should I use?
I looked to my card, and saw that on the memory chips it's written:
SAMSUMG 519
X4J55323QF-GC16
AWC900AAS

Well I got all ready for the flash.
But I cant find a way to boot up the PC with the GPU connected, and monitor plugged into the onboard video.
The PC freezes after the motherboard logo appears
Is there any BIOS option or way to make it just boot DOS ?