New build (Z170 Extreme4) dual channel issue?

I'm having an issue with a new system and I would really appreciate any suggestions.

AsRock Z170 Extreme 4
Corsair CMK16GX4M2B3000C15 Vengeance LPX 16 GB (2x8 GB) (not on list)
Intel i7 6700K
ASUS GeForce DUAL GTX1060 06G
EVGA 650 W GQ Series
Samsung 850 EVO 500GB (disconnected)

The system will not boot with both sticks in either of the dual channel configurations... a2/b2 or a1/b1. It will boot with both sticks in a1/a2 or with a single stick in a1 or a2. It also does not boot with a single stick in b1 or b2 although I'm not sure if this is normal?

I get a boot loop and the debug displays 00>19>00>16>4C. I have tried BIOS A/B and several resets including the full 4 hour battery out method. Tested the following versions:

3.20 (shipped)
7.00
7.10 (beta)

Both sticks happily run at 2133MHz or 3000MHz individually and with both installed in single channel mode (a1/a2), but without any successful dual channel boots I can't play with frequencies or voltages.

I was thinking it might be incompatible memory, a bad pair, faulty slots or CPU, but without alternatives to swap out I was going to order a memory kit from the approved list... unless I'm missing something? I suppose I should have done that in the first place, but I have seen plenty or reviewers happy with this board/memory and plenty of others using memory not on the list.



Edited by Alan80 - 28 Oct 2016 at 3:10am

Thanks very much for the info. I was going by the AsRock list and didn't think to check the Corsair one.

It makes me worried there is a problem with the motherboard then. I have tested each stick individually and they both work perfectly and the system boots. They also work together when in the first two a1/a2 slots... single channel mode.

Could it be a bad pairing? Just to clarify, the system won't boot with a single stick in either of the second two slots b1/b2... is this normal behaviour?

Xaltar wrote: No, that isn't normal behavior, ......My first stop would be to check the pins in the CPU socket, a bent pin could easily cause this issue and is more likely than a bad slot. Also check for any thermal paste/debris on the CPU pads.

Took those words right outta my mouth Xaltar did.

Well on closer examination I spotted what was a very slightly misaligned pin. I realigned it and took great care reassembling and mounting the Cooler Master Hyper 212X Cooler (unfortunately heavy/bulky) and I didn't tighten the spring loaded screws right up to stops this time.

Success! The system posts with an individual stick in all slots and also with the pair in a2/b2 or a1/b1. It's also happy running dual at 3000MHz XMP profile 1.

I'm going to give it some extentive testing and throw Windows on there, but I have lost a little confidence with the board... am I wrong? The mobo was a gift, but I would be OK with buying another if there was going to be some sort of problem in the future. What would you guys do?

Anyway, huge thanks for all the help and advice

Exactly what Wardog said. Bent pins on LGA (Land Grid Array) sockets is a very common issue, both out the box and user caused. The advantage of LGA is that if something breaks it is almost always the socket and the motherboard in most cases is far cheaper than the CPU (unless you bought a cheap CPU and high end board). I see why intel did it. Interestingly however, the socket is a lot more hardy than you would think. It is very difficult to actually break pins in an LGA socket due to their design. I bent a large number of pins on one of my boards when I accidentally dropped the CPU into the socket (it slipped), after a few hours with a magnifying glass and a razor blade I managed to get all the pins back in alignment and the board fired right back up and still works to this day.