Good idea, running a 1066Mhz cpu @800MHz +higher TDP (watts)

[Charly5]

Hi all experts,

as my northbridge PM45 just supports a FSB of 800MHz in conjunction with DDR2 RAM, I'm wondering, if I can use a cpu with 1066MHz@800MHz, which has quad instead of dual core, 45W instead of 35W TDP.

Will this cause the cpu run on lower GHz as well or only the FSB at 800MHz or will not run?

What will happen to the executed Watts and heat, running a 1066@800MHz FSB?

Now I do have a Core2Duo T5800
http://www.cpu-upgrade.com/CPUs/Intel/Core_2_Duo_Mobile/index.html

can I use:
http://www.cpu-upgrade.com/CPUs/Intel/Core_2_Quad_Mobile/index.html
or one of these
http://www.cpu-upgrade.com/CPUs/Intel/Core_2_Extreme_Mobile/index.html
or
a T9900
http://www.cpu-upgrade.com/CPUs/Intel/Core_2_Duo_Mobile/T9900_(Socket_P).html

Or better to stay at a original 800MHz FSB cpu like the T9500 ?
http://www.cpu-upgrade.com/CPUs/Intel/Core_2_Duo_Mobile/T9500_(Socket_P).html

Thanx a lot.
Cheers