hi guys , i'm thinking to buy a SONY VAIO Z – FW37GY

but was wondering whether the built-in 4GB RAM was DDR2 or DDR3, can anyone help me out ?

i have check the intel & sony website but couldn't get any answer
i also came across that the intel PM45 chipset was able to support DDR2 & DDR3 platform, how does it work ? able to have both type at the same time ?