I replaced my CPU heat sink with a Zalman nps 9900 max CPU cooler. Now when I try to start my computer I get a black screen. System specs: os is windows 7. Radon 6850 gpu. Ocz mode stream pro 700 w psu. Amd fx 6100 CPU. And motherboard is a gigabyte 990fxa-ud3. I have tried reseating the CPU gpu and plugging in all of the cables again including sata cables. I have also tried resetting cmos and reseating the ram. Any ideas would be greatly appreciated to remedy the issue.