Which of these socket A chips will user the least power and give off the least heat?

[MikeHunt79]

I've got

1) Athlon AXIA 1000Mhz

2) Athlon XP-M IQYHA 1800Mhz 35W (1.35vCore)

Plus a few normal athlon XP's.

I'm building a passive rig and I want the socket A chip which produces the least amount of heat. I don't mind downclocking...

 

[krooton]

The 1Ghz AXIA runs at 1.75, so the mobile chip would be the best

 

[MikeHunt79]

Ok, thanks... I seem to remember getting the XP-m chip running at 1.2v when underclocked, so I'll go for this.