Thank you for contacting the Intel® Communities.
I would like to provide you with the memory types that are supported by the Intel® NUC Kit NUC5i5RYK (DDR3L-1333/1600 1.35V SO-DIMM).
Now, your RAM modules should have a sticker with the part number this part number regularly starts with letters and also has numbers, if you search that in Google, you should be prompt with the manufacturer website and the specs of the module.
After finding the correct module specs, you should be able to verify the compatibility with the NUC (DDR3L-1333/1600 1.35V SO-DIMM).
If you would like to, you can provide me with this part number so I can check this.
Troubleshooting steps that you can perform:
1. Test each RAM module in each DIMM slots.
2. Test the system with different RAM modules.
I look forward to hearing from your outcome.
Here's my RAM module: TED3L8G1600C11-SBK, which should be perfectly compatible with the NUC (DDR3L-1333/1600 1.35V SO-DIMM)
I tested part of the trouble shooting steps, and it turns out to be:
1. each RAM module in the lower DIMM slot works. but when move to the higher slot, it doesn't work.
2. Currently I do not have different RAM module to test the system.
Do you have any idea what's going on?