Alienware M15x replaced thermal paste and now laptop won't power on

This is my first post so I apologize if this isn't the right place to post this topic.
Before I begin to explain my problem, my battery has not been able to be detected for over a week and I troubleshooted every way possible and nothing has worked so the computer has to be plugged in at all times. These are my system specs:

OPERATING SYSTEM:
Windows 2.6.1.7601 (Service Pack 1)
CPU TYPE:
Intel® Core™ i7 CPU Q 720 @ 1.60GHz
CPU SPEED:
1.62 GHz
SYSTEM MEMORY:
4.28 GB
VIDEO CARD MODEL:
NVIDIA GeForce GTX 260M
VIDEO CARD MEMORY:
2.93 GB
VIDEO CARD DRIVER:
nvd3dum.dll
DESKTOP RESOLUTION:
1600x900
HARD DISK SIZE:
249.95 GB
HARD DISK FREE SPACE:
95.71 GB (38%)
DOWNLOAD SPEED:
1.55 MB/s (12.4 mbps)

First off my laptop has been running a lot of games slow and at absurd temperatures reaching over 90 F. So I finally decided to take my laptop apart through a youtube guide video on the m15x tear down video. I cleaned the GPU heatsink and there was a lot of built up dust and decided to wait on cleaning out my CPU while waiting on new thermal paste. After I put my laptop together, I can notice a huge difference on the laptop on the GPU side. The fan was actually cooling my GPU and it wasnt just blowing hot air and making my laptop super hot on that side. Most of the games I play have been running a lot smoother and I can tell that what I have done has fixed some of the issue and it was noticeable that what I did had an impact on my laptop. The CPU side is was still running a bit hot and I couldnt wait for my thermal paste to come. After my thermal paste arrived (Tuniq X-2) I have watched vidoes and precautions on how to remove the old thermal paste and how to apply the new one. After watching several methods, and the do's/don'ts, I have finally applied the thermal paste on my CPU and the process went smoothly. I then put my laptop back together making sure everything was in their right spots and nothing was wrong. After turning my laptop on I decided to load one of my many games, Sims 3 and see how that will run with my new changes. Sims 3 was one of the many games I could not even handle due to how hot the laptop was getting. The loading was a a little bit faster and once i got into the actual game everything was running smoothly and I was surprised. After about half an hour the laptop froze. When i tried to power my laptop back on sometimes the screen would be all black or sometimes it would turn on and when i try to download any files or reload my game it would freeze. It came to the point where my laptop wouldnt turn on so i automatically started to check if my RAM sticks were bad. The same problem happened, sometimes i would get to the desktop screen and freeze or dont start up at all. I decided to go with trying to see if the RAM was the problem first because my laptop was only detected 2GB or RAM instead of 4GB of RAM. The laptop continued to recognize only 2GB when i had 4GB. Then the real problem started happening when all of a sudden when I try to power on my laptop the CPU fan isnt turning and when i hit the power button the laptop would power on for 1 split second and then turn off, then after 3 seconds it would try to power back on for 1 more second and then turn back off for another 3 seconds and it would keep repeating the process until i unplug the power cord since i can't run my laptop through my battery since holding the power button doesnt work since its doing this flashing on and off i dont have enough time to power it off like that.

 

Try without the HDD and with a different video card if it is possible for you.