New homebuilt computer turn on for brief secound the shuts down

[Zanarisrobo]

Alright, yeasterday i got my computer parts, and it worked perfectly fine even tho'its my first build. But today i noticed that my HDD wasnt detected, only the SSD. So i opened the case, fiddeled a bit with the SATA cables and rebooted the computer. When i reboot i see my fan spin for a brief second and the LED flashing briefly. I tried making the SATA cables like they were originaly but no effect. After looking around on forums i found a possible solution which was 1. take out the RAM sticks (I got 8x2) 2. pop the CMOS battery and flip it 3. put the RAM sticks in the slots they were in 4. Press the power button several times. And that worked, so i turned the computer off and got all the wires into their places and inserted the GPU card. And then i try to boot the computer, same problem. I tried using the CMOS battery method again without removing anything, it does not work. Which leaves me to think its either the GPU or some of the cables.

Specs:
MOBO- asus p8 z77-v le plus
CPU- core i5
GPU- radeon hd 7850 windforce OC 2gb
RAM-Corsair XMS3 8x2
PSU-Corsair TX750 M 750w

Help please

 

[AMD Radeon]

it could be anything

this one is really long tips but it can save you from getting headache
http://www.tomshardware.com/forum/261145-31-perform-steps-posting-boot-video-problems

 

[Zanarisrobo]

it could be anything

this one is really long tips but it can save you from getting headache
http://www.tomshardware.com/forum/261145-31-perform-steps-posting-boot-video-problems

I tried these solutions earlier today. But still, no effect

 

[Zanarisrobo]

I managed to isolate the problem, i took the computer apart then assembeled it again. And it booted nicely until i plugged the molex and Sata cable into the dvd drive. And considering the problem occured when i fiddeled with the SATA cables on my Hard drive it hasto be something with the SATA cables

 

[AMD Radeon]

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