Just enter here...

Why is it important to cool the chip of the motherboard???(the one with the green scuare on top of it in my P3V4X???)

For the same reason it's important to cool the cpu or graphics card chip - for stability. The chip on the mobo is the chipset that deals with all the major functions on the motherboard, interfaces between different parts (I dunno exactly what it does, but you get the idea - it's important!). Especially if you're having stability problems, better cooling of the mobo's chips could help - that's why abit puts active cooling (fan and heatsink) on it's mobos.

The P3V series benefits from a small heatsink on the clock chip also. Especially if you are using a high FSB.

Can you be more specific on the "clock generator" thing???