As explained in the title this is my first build i finished today with putting everything together. When i go to power it on I get no image on the monitor and the fans (case, cpu, psu, gpu) all start spinning and running fine for about 30 seconds then the computer powers off by its self for about 3-5 seconds turns back on and continues running for about another 30 seconds (this continues to happen till i turn it off).
What did I do wrong/ faulty part?
We have a troubleshooting checklist that was created to troubleshoot this exact type of problem. There's a link to the checklist in my signature. Perform every step in the checklist and it will help you find what's causing the problem.
the motherboard is a gygabyte GA-Z68X-UD4-B3 Z68
the cpu is and i5 2500k on standard heat sync
the ram is gskilled 8gb 1600 ram kit
the gpu is a sapphire vapor x radeon hd 6870
the hdd is a hitachi 1.5tb at 7200rpm
and the psu is a antec 750w high current gamer power supply
And isn't breadboarding like the same as a bench build? And I have no idea if I am getting a post beep this is my first build so I dont have one of the motherboard speakers and my motherboard didn't come with one
Yes, breadboarding is testing the system outside the case to eliminate the possibility of a short.
There's a link to a site where you can get a cheap system speaker in the checklist. It's very hard to troubleshoot a problem without being able to hear the beep codes.
So you have both 6-pin PCI-E connectors plugged into the GPU as well as the 24-pin main motherboard power connector and the 8-pin CPU power connector? Have you tried each stick of RAM by itself in every RAM slot?
I really don't have any suggestions that aren't already in the troubleshooting checklist. There are suggestions from many knowledgeable forum members in that checklist. As new issues were identified I added them to the list. I highly recommend picking up a system speaker so you're not taking stabs in the dark.