I have been unable to get tga2vtf to not compress a texture. I have followed the directions by including a .txt file with the line $nocompress in it, but it didn't work.
You must have really good eyes to see that it didn't work. Why do you want to make an uncompressed texture? The only thing I could think that would be usefull is for gradient ramp and even for that it's not necessary.
I need it for a normal map for some small tiles. The compression is creating ugly looking squares in the normal map that mess up the lighting. To be sure it wasn't working, I tried it compiling a gradient ramp, and sure enough it's still getting compressed.
SOLVED: Instead of putting $nocompress in the txt file, put "nocompress" 1 in the text file. Then I added "nolod" 1 and "nomip" 1 to it for good measure and it worked.
You should post before and after screenshots to show people the negative effects on the normal map (I certainly would like to see it). Also, if it is uncompressed, it is going to take up a lot more memory.
This is a tradeoff you have to take into consideration. If you'd use nocompress for all the textures id kill your video memory but for only one texture it should be ok.