peltier question

ok i have been thinking about geting a pelt to cool my cpu a bit more then my water cooling is right now but my question is do i need to have a coldplate to use a pelt or can i just put the pelt between the cpu and the waterblock? i need to know because i might need to get a new waterblock also if i need to use a coldplate. my waterblock uses the socket lug to hold it down so i cant use a coldplate is why

Yes you need a coldplate and some way to attach it to the block independently of the cpu retention. Pelts need a lot of force (150-200 psi), cpus do not.