CPU light on, no display, new heatsink

I just installed a 12mm sidon liquid heatsink from cooler master and have ran into many issues. Whenever I boot I sometimes get no signal (recently) and when I do it will randomly freeze, also the CPU light is on but I have low temps.

I will begin: I installed this heatsink following textbook procedure, (removing mobo, putting backplate on, pea sized glob of thermal paste, mount and test) However when i booted it would stop and restart several times. After restarting it (roughly 7 times) I was able to launch but windows 7 froze, I was forced to restart. Once I did I got a little further, (setup complete, launched chrome) and it froze again. I then decided to check my plugs and mount, I reinstalled the heatsink with a new layer of thermal paste(yes I removed the old layer). I got it working fine, temps roughly 22 C, never went under load. After restarting however I ran into the problem of it not being able to launch and getting stuck in a launch-re launch cycle. I then looked at the connections and they seemed fine, also the CPU light being on is peculiar because I was able to sustain 20 C when the computer was on. I have been running this build on my computer for over a year and recently got this heatsink, and heatsink only.

My build is as follows:

CPU: i5 2500K
GPU: EVGA GTX 570
Mobo: Asus P8-z68 pro
Ram: 16 GB Corsair
650 watt PSU Corsair

I am infuriated right now and am at a loss without one for finals.