one lil question about shaders.. and about GeForce crashing my pc...

hi dudes, i am tring to understand vertex and fragment shaders, and i came across a little detail that i can’t understand:
what does it mean “swizzling” in shader language?? In the spec files no one cares to explain it.
After that a little question, just 4 my personal concern (i hope not to go too much off topic). I have an amd k7 1GHz, via kt133 chipset, and i bought a geforce4 fx. Now as soon as it process 3d info, the pc hangs and crashes. did anyone come across the same prob?? How can i solve?
thank you all guys. Bye

Swizzling is when you replicate some components of a source register into different components of a destination register.

Ex.: src.xyzw = dst.xxyy

Will do:
src.x = dst.x
src.y = dst.x
src.z = dst.y
src.w = dst.y


simple and clear,
thx Y!

Somebody tricked you, there is no GeForce4 FX