A new type of electrical memory based upon AgGeSe thin films was recently proposed. The Programmable Metallization Cell is ananometric Ni/AgGeSe/Ag cell which electrical characteristics undergo drastic changes (resistive/conductive) upon electricalpolarisation. A clear understanding of the phenomenon underlying such a change is still lacking. Our team has recently carried out aseries of investigation on the Agx(Ge0.25Se0.75)100x bulk glasses (x < 30 at.%). Their conductivity changed suddenly by 7-8orders of magnitude for x ~ 10 at.%. Phase separation has been evidenced by electrical force microscopy and field emissionscanning electron microscopy. Different Ag-Ag correlations depending on Ag content in the glasses were shown by combinedneutron scattering (D4) and ab initio molecular dynamic simulations.In order to go further in the understanding, we now propose to elucidate the miscible character in the liquid state at differenttemperatures.