Atmega2560V, trying to burn bootloaders of MegaCore I am trying to burn MegaCore bootloaders to it, I have setup my custom PCB  with Atmega2560V-8AU and 8Mhz Crystal + Load Caps all assembled on using PCBA process.
I am trying to burn MegaCore bootlaoders to it, I am using Arduino UNO as ISP Programmer. My connections are all correct, It shows different Device Signatures (see below) whenever I hit Burn Bootloaders....


  0x0000ff
  0x00003f
  0x0000ff
  0x00ff00
  0x001000
  0xff0000
  0xfc0000
  0x00fe00


This is complete output with different Device Signatures


  Arduino: 1.8.3 (Windows 10), Board: "ATmega2560, Arduino MEGA pinout,
  2.7v, Disabled (default), 8 MHz external"
  
  C:\Program Files (x86)\Arduino\hardware\tools\avr/bin/avrdude
  -CC:\Users\mudas\OneDrive\Documents\Arduino\hardware\MegaCore-avr-100-pin\avr/avrdude.conf
  -v -patmega2560 -cstk500v1 -PCOM4 -b19200 -e -Ulock:w:0x3f:m -Uefuse:w:0xfd:m -Uhfuse:w:0xd6:m -Ulfuse:w:0xf7:m 
  
  avrdude: Version 6.3, compiled on Jan 17 2017 at 12:00:53
           Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
           Copyright (c) 2007-2014 Joerg Wunsch

     System wide configuration file is "C:\Users\mudas\OneDrive\Documents\Arduino\hardware\MegaCore-avr-100-pin\avr/avrdude.conf"

     Using Port                    : COM4
     Using Programmer              : stk500v1
     Overriding Baud Rate          : 19200
     AVR Part                      : ATmega2560
     Chip Erase delay              : 9000 us
     PAGEL                         : PD7
     BS2                           : PA0
     RESET disposition             : dedicated
     RETRY pulse                   : SCK
     serial program mode           : yes
     parallel program mode         : yes
     Timeout                       : 200
     StabDelay                     : 100
     CmdexeDelay                   : 25
     SyncLoops                     : 32
     ByteDelay                     : 0
     PollIndex                     : 3
     PollValue                     : 0x53
     Memory Detail                 :

                              Block Poll               Page                       Polled
       Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
       ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
       eeprom        65    10     8    0 no       4096    8      0  9000  9000 0x00 0x00
       flash         65    10   256    0 yes    262144  256   1024  4500  4500 0x00 0x00
       lfuse          0     0     0    0 no          1    0      0  9000  9000 0x00 0x00
       hfuse          0     0     0    0 no          1    0      0  9000  9000 0x00 0x00
       efuse          0     0     0    0 no          1    0      0  9000  9000 0x00 0x00
       lock           0     0     0    0 no          1    0      0  9000  9000 0x00 0x00
       calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
       signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

     Programmer Type : STK500
     Description     : Atmel STK500 Version 1.x firmware
     Hardware Version: 2
     Firmware Version: 1.18
     Topcard         : Unknown
     Vtarget         : 0.0 V
     Varef           : 0.0 V
     Oscillator      : Off
     SCK period      : 0.1 us

  
  avrdude: AVR device initialized and ready to accept instructions
  
  Error while burning bootloader. Reading |
  
  ############################################ | 100% 0.02s
  
  avrdude: Device signature = 0x00fe00 avrdude: Expected signature for
  ATmega2560 is 1E 98 01
           Double check chip, or use -F to override this check.
  
  avrdude done.  Thank you.


This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.
What should be the problem.??? How to solve this.?
I removed 8Mhz from board and followed this instructions LINK, and burnt bootloaders using -F override check, then i returned 8Mhz oscillator to Atmega2560V and see device signature and it's automatically appears 0x1e9801 rather than 0x1e9803