Most likely a cracked solder-joint somewhere.
Start by looking around stuff that gets handled, like connectors and slots.
But check for obvious damage first =)

I have a 2176-c65 that had a similar issue. It ended up being a bad connection between the riser and the motherboard. Apparently the recommended connection order is connector pieces in the riser first, then install I. The motherboard. Once I took it out and put it back together in the right order all was good!

I cannot recall if I had the same beep code though, but I did have one. I can check and see if I can replicate it in the next few days if you can wait that long.

Thanks for the replies guys. I ended up ordering a spare later revision motherboard and of course it was DOA. However, I did find a screw behind the motherboard between it and the case that someone has dropped at somepoint so maybe it was shorting something out. Since doing a full removal of all the components and a reinstall it so far is working great. Knock on wood haha.