I finally got the MB back from Gigabyte. They sent the same board back. There was no indication as to what they found, what they did, or anything.
...and the board is doing the exact same thing! ...constantly rebooting!
My friend, who's a network administrator, took an i5 CPU from a working machine & tried it in the board. We shorted the CMOS jumpers to reset the BIOS before testing it.
This CPU seemed to work at first (no rebooting), but it just seemed to hang, and there was no output to the monitor. We plugged in a MB tester & it gave an error code indicating a problem with the CPU, but we were using a WORKING CPU.
Now I'm wondering... does Gigabyte actually TEST boards that have been RMA'd (install RAM, plug them up to a monitor, go through the boot process, etc...), or do they just voltage test them?
I was thinking of returning my CPU, but I'm not totally convinced that this MB was tested properly by GB, and I'm betting that it's still bad. If the MB is OK, then why didn't the i5 work? ...and I'm really confused that the i5 and my i3 act differently (i3=reboots, i5=hangs), but ultimately they both won't work in my MB & don't display any video output.
Unless there's something we're missing, this board still seems bad.
Does anyone have any other advice or info that might help?
Thanks!