We are experiencing a problem with NUC7i5BNH running with two 16GB SO-DIMMs. After updating the bios from the original 42 to 57 the unit powers up really slow from cold state. It takes about 45s-1min to reach the Intel NUC logo page and it takes several seconds until the "F2/F7/F10" texts appear. Normally all this happens in <10 seconds pressing the power button.
A post error message "(a7) me fw downgrade request mespilock failed" is briefly displayed before the boot process is started. Warm restarts seem normal (=fast) and the memories pass Memtest normally. The unit seems to operating normally besides the very slow cold boot and the post error message. We definitely cannot deliver the unit to a customer in this condition.
We have reproduced the problem with two NUC7i5BNH units. On the second unit we did everything in a very controlled manner. The unit worked perfectly with the 42 version; all problems appeared after the update to 57. I do realise that the problem might be some incompatibility with the Corsair memories but they work individually and also pass memtest together after the slow cold boot has finished. I really hesitate to spend ~400eur just try out a second set of memories.
- BIOS update with proper "Reset bios settings to defaults" after the update
- Tried bios recovery with jumper and power menu methods -> no effect
- Tried with memories individually in either slots -> worked fine without problems (fast, no post error)
- Tried different (Kingston, Adata) smaller memories individually in the unit -> worked fine without problems (fast, no post error)
Things not tried:
- Different 2 x 16GB modules. Unfortunately we do not have Kingston/AData 2133MHz 16GB modules available. We could get our hands on 2 x 16GB 2400MHz Adata. However the memories are really expensive to just try out. The Corsair modules themselves pass memtest and work individually in the same units. Also their specifications meet the requirements stated in the Technical Product Specification.
- Any smaller memories in dual channel configuration. We have a chance for this on Monday. However it does not really help us to find out that 2x4 or 2x8 works.
- Downgrading BIOS to anything earlier to 57 (see BIOS downgrade question below)
Intel NUC7i5BNH original BIOS 42 updated to 57
No SSD installed at the moment (AData SX8000 will be installed once the memory problem is solved)
BIOS release notes state that you could downgrade from 57 -> 54: "Due to a security enhancement, it will not be possible to go to any BIOS earlier than BIOS 0054."
However the BIOS update readme states the following: "If you are trying to downgrade to a previous BIOS version and its Intel® ME Firmware version is older than that currently on the motherboard, then the downgrade is NOT supported."
The ME FW in 57 is newer than in 54 (184.108.40.20625 vs 220.127.116.1164). Is the downgrade to 54 allowed/supported or not?
- What is this post error message "(a7) me fw downgrade request mespilock failed"? We have definitely not downgraded anything. Is the unit internally trying to perform some kind of revert to previous bios when the post is taking too long? Could not find any google hits on NUC with this error.
- Is the BIOS downgrade from 57 to any previous version allowed/supported? Since the documentation would indicate that we cannot downgrade (see above), we seem stuck with 57.
- Has any of the relevant BIOS settings changed between 42 to 57? These do not seem to be listed in the release notes.
- Are there any BIOS settings we could try to change? Eg. memory timings or the "Round trip latency optimisation".
- Anything else we could try?
We provide Intel NUC solutions as a business and have installed several hundred units since 2013. This is the first time we experience this kind of problem. We have also provided NUC6 and NUC7 units with 32GB memory without problems but the NUC7i5BNH+Corsair 2x16GB combo is our first.
Any help is well appreciated!
Henri / TeraStore