Kingston - Memory - 512 MB - DIMM 240-pin @ Harris $99 + 2.25% cashback
Its compatible with a variety of Sony Vaio, Packard Bell, NEC, Gateway, Acer desktops. Check full compatibility at Kingston
When there do a memory search by Part Number (drop down box top RHS of window) and enter D6464F50 in the Kingston # box.
Dont forget to login to get the cashback.