thanks for replying!!
I took a chance and ordered segate momentus 320 gigs sata and guess what it went through smoothly.
Actually, I am having windows vista home premium and the hdd I replaced was a Hitachi 80 Gigs, I read the datasheet for my model, and it was a "certified" SATA
The only reason why I was not sure was that no where it said SATA, I had to decode the model number terminology something like "HTS...".
I also ordered one SATA to USB converter (USB powered Y cable) and my old 80 gigs is working as an external HDD (just 4 bucks ebay).