Laptop rebooting at BIOS Splash Screen

[wh1t3l1ghtn1ng]

I am repairing a Samsung R730 for a friend. The laptop keeps rebooting at the BIOS splash screen. I tried swapping out ram and booting without battery, hard drive, or optical drive. I also disassembled the laptop and cleaned/applied more cooling paste to the CPU and GPU. This produced the same results. I ordered a refurbished motherboard and cpu off the internet. I swapped the hardware tonight and same issue persists. I am lost on next steps. Any assistance will be appreciated.

 

[diamat98]

Check the usb ports and see if any of the ports is busted. I've fixed other laptops previously and when the pins from the usb are bent they tent to provoke this problem

 

[wh1t3l1ghtn1ng]

No damage to the base and no damage to ports or pins.