I don't see a beep sequence with 5 beeps, but there is an 8 beep sequence, and it's the only one listed that also shuts the NUC off:
16 on/off blinks (8 beeps)
.25 seconds on, .25 seconds off, .25 seconds on, .25 seconds off, for a total of 16 blinks.
Then the computer shuts down.
CPU thermal trip warning
Check that chassis ventilation holes are not blocked and unit has sufficient airflow.
If that's the issue, then you're likely looking at a bad unit.
It's always worth a try to check the memory (verify it's compatible, try one stick at a time).
Hope this helps.
No display with new Intel® NUC Kit 5i3MYBE. Please verify if you selected the proper video input in your monitor (TV). It is recommended to use straight DisplayPort video cables (high quality) and use 1 memory stick.
Try to connect your NUC with any other monitor just to narrow down the issue.