Yes, I came to Gigabyte from Asus myself and I know just what you mean.
I got the Mobo back today from Gigabyte UK after it was tested and found to boot OK with F2 BIOS and 4790K. But they still gave it a full update of BIOS and backup BIOS to F4 and after some other tweaks my end it now works fine, 4790K CPU correctly recognised in default BIOS which is great and with XMP enabled the G-Skill 2400 RAM also works to spec.
I reset the PSU by toggling the on/off rapidly as per manual and also cleaned a strange film on the underside of the CPU covering a few contacts, which may have helped with my end.
However I have a confession to make and an important addition to this thread for future reference for anyone troubleshooting this mobo. I have just realised that
this mobo definitely needs one stick of RAM to POST. Some people may think this is obvious, I honestly didn't know. My tests with RAM installed all failed at first due to socket damage so I was not able to tell if it needed RAM or not.
When reducing the loadout to minimise variables after finding the initial fault, (which I did mention in a
previous post which unfortunately noone noticed here or anywhere else I mentioned it, as people probably assumed noone would be that dumb
) I took out all the RAM so it could not POST even if everything else was OK, though there is no way of knowing if it was OK or not. *facepalm*
I have confessed details to my retailer SCAN and Gigabyte support for future reference and offered to reimburse any costs incurred by my own error. Though the critical test which lead to mobo replacement was fortunately done with RAM in so I think I am in the clear on that one as that was socket damage.
So you live and learn, but Gigabyte's support really has been good and I am just happy to have a nice updated backup BIOS.
Thanks also for the constructive input offered here.
