Can't upload sketches on 328-PU on Arduino Uno Rev3

Using Arduino Microcontrollers
1

Hi,
Recently I bought some ATMega 328PU microcontrollers. The chips came preloaded with Uno bootloader and blink sketch. My problem is if I remove my stock 328 P-PU and insert the new 328-PU into my Uno R3, I get error message. I have also tried to upload without & with editing the signature from 0x1e 0x95 0x0F to 0x1e 0x95 0x14 in the avrdude.config. I am not able to upload any sketches to it. Nor can I burn a bootloader on these chips by following the procedures mentioned. All I have is the blink sketch running by blinking LED on pin 13.

  1. following is the error message (without changing signature)- avrdude: Expected signature for ATMEGA328P is 1E 95 0F
    Double check chip, or use -F to override this check.

  2. following is the error after editing signature- avrdude: Expected signature for ATMEGA328P is 1E 95 14
    Double check chip, or use -F to override this check.

I do close the IDE and restart it after editing the avrdude.config file.

I have the following IDE versions a) arduino-1.0.1
b) arduino-1.0.2

I do not know what else to do. Please help.