it looks like you indeed do have the newcastle rather than the winchester core... The "technology" field shows the core of your processor, The newcastle is 0.13u where as the winchester shows up as 0.09u ... are you sure you got a winchester? Did the supplier perhaps give you the wrong chip? I have a winchester and it shows up as 0.09u, i didnt have to flash the bios for that.
I have noticed though that you are using an older version of cpu-z than me... maybe that version doesnt recognise the winchester... download a more up to date version and try that!
here is what I see on mine!