So, apparently, my computer got messed up ever since I installed the client (back when it's 1.2.)

Generally, I wasn't experiencing any problems at first, however, things got complicated overtime. Some days after the client installation, my computer started to become harder to turn on (Turns off when I press the power button for the first time of the day) and resets every now and then. It is sometimes in a pattern or unpredictable. The computer crashes more when I enter TF2. I couldn't even go into XJZ servers due to the computer crashing upon connecting, however, there are sometimes I can get in and play (for a short time rather).

EVERYTHING got worse overtime. Immediate crash when entering a TF2 Server, crashes on a few minutes interval (1-5 minutes or so), 10+ power button pushes just to enter the blue start-up screen (then crashing on a few seconds)

I'm pretty annoyed by this since I hate letting the computer go for repairs. The laptop I'm in can't even run Steam (Can run DOTA 1 though :P) I missed seeing my friends on my favorite servers. I essentially need advice right now on how to fix this or fix my temper xP. Seriously though, I need help from the darned community