|Try blowing out the vents on the bottom using canned compressed air. The unit may be overheating. |
I doubt the power pack and battery were the problem. Bad advice from the vendor IMO.
Also try booting into Windows Safe Mode with networking by tapping F8 at start up. If you can get things to run for a while then download HWMonitor to monitor the temperatures and voltages in real time. This will tell you if you had/have a power issue or an overheating issue.
Get HWMonitor from the link below.