These might be a better question
@Knoxx29 for
@HUSKIE. If Huskie bought the hardware from his friend and saw it working, we may be able to make some assumptions about what it could be.
- Did you pick up the computer from your friend or was it shipped?
- Was the CPU in the socket of the motherboard when you received it?
- Was the DRAM in the motherboard when you got it or was it off to the side?
- Did you see it running with the same combination of hardware (if items were excluded, can you point them out?)
- You're getting no post codes (no 7-segment display to get them, is there a header for one?) and no beep codes, correct?
Yeah mobo,CPU,Ram, psu and gpu
Not a chassis? So only the CPU and memory could have possibly been installed during transit? If that came to, was the cooler mounted during transit?
This might be a long shot but, if a different CPU was in the motherboard when you saw it running and if the motherboard has the original BIOS, the 3820 might be incompatible without a BIOS update. The 3820 came out after the 3930k and 3960x did and several earlier boards needed a BIOS update to support it. My own experience with an older BIOS with my P9X79 Deluxe is that the DRAM can also be the culprit. Usually when my machines fail to boot after doing work on them, that's the cause. You mentioned that you tested with a single DIMM, did you try different DIMM slots instead of using the same one all the time? Bad contact with the pins on the socket or the DRAM slot can result in DIMMs getting detected but, actively being flagged as having issues (I've seen this on my own P9X79 Deluxe' as well.)
Also, don't over-tighten coolers on X79. That CPU is resting on a lot of pins (It's called skt2011 for a reason, there are 2011 pins/contacts) and I highly suggest gradually tightening up each corner at least 2 passes, preferably 3, before tightening it to where you want it. I have found this to cause issues with DRAM slots if done carelessly.