is my chip burned?

Hi, i bought a 328P-PU and connected it to the socket on my duemilenove. The led (13) starts blinking but i cant upload new code nor burn (re-burn) bootloader.
i get the error “avrdude: stk500_getsync(): not in sync: resp=0x00” both trying to load new code or burning bootloader.
When i replace the new 328 with the one that came with the board everything works as expected.
Is it burned(broken)?
If it is, is it possible that the led from pin 13 still blinks anyway?
Thanks

What are you using for an ISP device when you attempt to burn the bootloader?

What bootloader (if any) did the ATmega328P come pre-burnt with? If you aren't sure, try selecting some of the other Arduino types like the Duemilanove and UNO. Their bootloaders use different data rates so you can't swap the chips without using the different "Board" identifier.

Hi, i bought a 328P-PU and connected it to the socket on my duemilenove.

Without the bootloader or burning the bootloader first? Then you have to burn bootloader to this ATmega328 because it can be one of reasons, an error "avrdude: stk500_getsync(): not in sync: resp=0x00" (missing a bootloader).