Nvidia 9600GT on a 350w PSU

[iicookie]

As the title says, I want to change my old 9400GT to a 9600GT. But the problem is, my PSU is only 350w. I plan on getting the 59w version of the 9600GT but will I get any problems when playing games?

If theres any info you need, tell me, thanks!

 

[iicookie]

I have thought about buying a 9800GT, but the store closest to where I live is out of stock. They only have the 9600GT left.

And thats another thing. What and where is this "12v rail" and whats "amps"? I've looked everywhere in my computer. I tried googling images, and i see these cables, in which I can't find in my computer.

Sorry, I'm bad at computers. Please help!