Cannot flash firmware and freezing on new printer- Anet A8

[-Will-]

Hello everyone, I'm will, and new here (first thread )

I have a good amount of experience with various 3D printers at school as part of my robotics team and have finally decided to purchase my own machine. I chose the Anet A8 because it is cheap, customizable and popular amoungst other penny-pinching hobbyists. However, I am having some issues wich are preventing me from using the printer. Those issues are that I cannot flash the firmware and the printer frequently freezes soon after startup.

I want to flash the firmware because the printer likely ships with an outdated version of marlin that doesn't have the thermistor checks. I have tried to upload the latest version of marlin to my machine, using the proper configuration files and board in the Arduino IDE, without success. The error messages it gives me are either "the selected port was either disconnected or does not exist" or more commonly, this copy-paste from the Arduino error message:
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Sketch uses 104096 bytes (81%) of program storage space. Maximum is 126976 bytes.
Global variables use 4083 bytes of dynamic memory.
C:\Program Files (x86)\Arduino\hardware\tools\avr/bin/avrdude -CC:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf -v -patmega1284p -carduino -PCOM4 -b57600 -D -Uflash:w:C:\Users\wdwe_\AppData\Local\Temp\arduino _build_641910/Marlin.ino.hex:i


avrdude: Version 6.3-20171130
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch


System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf"


Using Port : COM4
Using Programmer : arduino
Overriding Baud Rate : 57600
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x00


avrdude done. Thank you.


An error occurred while uploading the sketch
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The printer also tends to freeze shortly after powering it up. By this, I mean that I will be navigating the LCD menu with the buttons on the printer and it will suddenly become nonresponsive. This is most frustrating when it occurs during heating and when I'm using the steppers for bed leveling.

To try and fix these issues I have tried:-Installing the CH340 drivers (no effect)
-Checking the power supply output (good at 11.8 - 20.0 v)
-Changing the printers baud rate from its bizarre default to the overriding baud rate in the Arduino error message (no effect)
-Power cycling (no effect)

I think the board I got is no good, but would greatly appreciate second opinions before pestering Anet for a new one.

~Will