Ramps Diagnosis? Bad Ramps? or bad power?

Hello, Ill add a youtube video a little later after work, but I'll give a description for now.

Hardware
Arduino Mega + ramps 1.4 combo

Printer Type: Kossel Mini, Delta Bot
LCD Screen with SD card
3 mechanical Endstops for the towers and +1 Optical endstop
3 Steppers + 1 Higher torque nema 17 rated 1.5a
E3d All metal hotend

Issues Observed:
- Stepper motors perform normal operation including extruder motor simultaneously with the hotend off.
- Steppers are off/idle, Hotend heats up and holds temp for 15+ minutes normally.

-Hotend and Steppers start executing print, Ramps intermittently turns on and off in what appears to be drawing too much power. Arduino Mega is executing commands normally due to usb.
-The intermittence lasts 4-5 minutes and then what seems to build up enough energy to continue printing operations normally. However this will cause the head to crash.
Power supply multimeter readings show 12v5a (laptop)

Any help from these descriptions would be appreciated.

My guess is the 5A polyfuse is tripping. Repeated tripping can derate the 5A value...or it could just be a flaky fuse. Either replace it with a new polyfuse, or replace it with a fuse holder and use automotive or glass-tube style fuses instead. A fan blowing on the polyfuse may help to cool it, extending the time it can be run as a test.