CPU upgrade for Asus N81vg currently running with P8600

[gs08367]

Hi All,

I am new to this so pardon my lack of knowledge in some things that one might regard as basic.

I am trying to figure out whether a 14-inch notebook currently running on Intel Core 2 Duo P8600 would work with a quad core of the same socket/chipset/FSB specs.

Potential CPU choices:
1) QX9300
http://www.cpu-world.com/CPUs/Core_2/Intel-Core%202%20Extreme%20Mobile%20QX9300%20AW80581ZH061003.html

2) Q9100
http://www.cpu-world.com/CPUs/Core_2/Intel-Core%202%20Quad%20Mobile%20Q9100%20AW80581GH051003.html

3) Q9200
http://www.cpu-world.com/CPUs/Core_2/Intel-Core%202%20Quad%20Mobile%20Q9100%20AW80581GH051003.html

Most eBay sellers give compatibility list mentioning a handful of laptops and stipulate that it will not work on a 14-inch laptop. I am trying to understand why it wouldn't.

Thanks & Kind Regards

[gs08367]

Current CPU specs
http://www.cpu-world.com/CPUs/Core_2/Intel-Core%202%20Duo%20Mobile%20P8600%20AW80577SH0563M%20%28BX80577P8600%29.html