Gigabyte Z170X Gaming 7 not posting after error

I am looking for some advice with regard to my GA-Z170X-Gaming 7 board. Built a new system three weeks ago (all to spec, no OC'ing) and all was fine. Yesterday while playing a game I got a hard crash BSOD with "WHEA_UNCORRECTABLE ERROR" and had to power the cpu off. Board now just goes into a restart loop and never completes POST. Diagnostic codes vary on restart but are generally C2, C3, C4, C5 (which in the manual are listed as "Reserved", though I have seen a code 19 and a 3E) before it restarts. I get no video (from my card or on-board) and cannot get to BIOS. I have followed the trouble shooting procedure, swapped video card & power supply, tried running with one memory stick (and swapping the sticks) but no joy. Also tried CMOS reset and removing the battery to get back to defaults.

Any advice would be greatly appreciated. Otherwise, anyone have experience with Gigabyte's RMA process?

Specs: Gigabyte GA-Z170X-Gaming 7 (I believe the bios was f6) ;
Intel i7-6700K
G.Skill TridentZ 16 GB DDR4 3400
Samsung 850 500GB SATA III SSD
Western Digital 3 TB Green HD
EVGA GTX 980 Ti 6GB SC Gaming

RMA with Gigabyte is painless and about 2 week turnaround.
3 weeks old, you should be able to return it to where you bought it.

Have u tried to flip the switch on SB to 2? That allows it to use the secondary bios. Fixed a issue i had with
my gaming 7 Till i flashed it to f6

Definitely try the second BIOS. If that doesn't work, it's dead. RMA with the place of purchase.

Unfortunately, Newegg caught me with their short term rebate (less than 30 days to claim) and I, of course, had to remove the UPC code from the packaging. Newegg policy will not accept an RMA without intact packaging. So I will have to see about an RMA with Gigabyte! In future, I will no longer consider or file for rebates when selecting where to purchase!

Thank you for your responses. Hopefully Gigabyte will be easy to work with!

Gigabyte historically has good customer service, you'll be just fine!

ATMINSIDE said:

Gigabyte historically has good customer service, you'll be just fine!

Click to expand...

I concur. I've never had any issues with RMA with Gigabyte.

+1 Gigabyte will do you right. There use to be a trick hold the reset button and power button at the same time and see if that will reflash the main bios.

Gigabyte has authorized the RMA of the board. I will return it and post here with what progress I am able to make in getting a stable system back. Thanks to all for your help!

That was quick!

I just purchased this board last week from Microcenter with a i5 6600k and Corsair Vengeance LPX 2666Mhz DDR4 RAM. It will not post video using a known working Monitor, HDMI cable, PSU, and using onboard HDMI video. Even resetting the CMOs, Moving SB from 1 to 2. Back to Microcenter we go it seems.

Well, here's the long sad story so far. Sent the MB back to Gigabyte and after two weeks got back what they call a "replacement/swap". Interestingly, the "replacement" MB came back in the same box with the same cables, etc. It does appear to have a new serial number sticker but the numbers are nearly identical to the board I sent back other a couple of leading digits. What makes me highly suspicious is the fact that the "replacement" board does exactly the same thing! Throws out the C2, C3, C4, C5 codes, reboots, repeats and ends with a 4C. Note, these codes are listed as "Reserved", but looking on line I found the EVGA Z170 debug codes and C0-CF are listed as OEM Boot Selection Device codes, and the 4C code appears to fall into the OEM post memory initialization.

Since receiving the "replacement" board I have remove the board from the CPU case, attempted to boot with each of the two DDR4 memory sticks, one at a time, in each and every memory socket, clearing CMOS each attempt with both the on board switch and by "shorting" the jumper before moving the stick of memory to a new socket. Results are the same, it never seems to clear POST with nothing ever appearing on screen (and this is with known working PSU and video card; nor do I get any video off of the board using the HDMI.


Though I hate to do it I am contemplating purchasing a different socket 1151 board (non-Gigabyte), a new CPU and new DD4 memory and then rebuilding the system starting first with a new board and all the "old" parts and seeing how it goes.

Otherwise, I am at my wits end with this board/system. Any suggestions would be greatly appreciated!

I dont supposed this would be caused by a damaged CPU. I have heard stories of people bending or cracking the CPU board against the socket. Im currently building a 6700k system and Im a bit weary of the thin board of the CPU and the amount of pressure when mounting the HSF. Its just a thought but I would check the CPU for damage.



Z

+1 look to see if the bottom of your CPU is warped.

Thanks for the suggestions. I will take a look at the CPU. But it seems strange that the system booted up for nearly three weeks before this issue started. When I reassembled the system yesterday I didn't notice anything amiss, but then I wasn't specifically looking extremely close as I believed the swapped MB might solve the issue.

As a thought, I note that there seems to be several posts, here and elsewhere, with various Z170 boards having issues with high frequency memory. My memory is G.Skill TridentZ 16 GB DDR4 3400. Further, on initial build the MB did not correctly recognize the proper memory timings and would not let me enter them in BIOS. Only when I selected XMP did the board default to the correct memory timings. I also updated BIOS at that time as it indicated better memory compatibility. Within a few days of these changes is when the board stopped POSTing.

Removed the cooler (a Corsair H80) and checked the CPU. CPU looks OK and doesn't appear to be damaged as recently reported regarding the thinner CPU substrate and legacy coolers applying too much pressure and bending/breaking the CPU. Though I note that Corsair has yet to respond as to whether their units (or which of their units) are compatible with skylake chips.

This is REALLY frustrating as I can now add uncertainty with using the H80 cooler to the mix of possible issues! But, thanks for your suggestions. Really appreciate it!

Well after that it sounds like from your research incompatible memory for some reason, unless they gave you the same board back, they did that with mine however it worked after receiving it.

Yeah, I really suspect that this is the same board with a new, slightly changed serial number. Out of a string of about 20 numbers/characters the serial number is nearly identical (even to match all of the last digits) with just a couple of leading characters changed. As mentioned, it was also returned in the exact same box with the exact cables and such I sent back.

Guess I'll have to break down and go buy a new, non-Gigabyte board and new memory and see if I can run down whether or not it is the board or the memory. Last resort will be a new CPU...Ugh!

Can't you just borror some memory, or take you PC to a repair shop and ask nicely how much to test different memory. I defiantly don't think it's your CPU.

Well...I've swapped PSU's, graphic cards, memory and motherboards and still cant get it to complete POST. So I guess I am left with what I thought would be the least likely issue and that is a bad CPU. The motherboard's seem to indicate that there is an issue with memory, but swapping memory modules results in the same diagnostic codes/indicators (I've now used the replacement Gigabyte board and an MSI Z170A board and neither complete POST).

Tomorrow I will see about replacing the CPU. If that doesn't work then I guess my days of building my own PC are finished (and I've done so since the early 1990's!!!!).