I have an old laptop, and tried to install OpenBSD-current on it. Unfortunately, no matter from OpenBSD 6.3 to upgrade, or install it from scratch. the machine couldn’t boot successfully. It displayed:
>>OpenBSD/amd64 BOOT 3.39
Then it flashed one line (I couldn’t see that line clearly, and it should display loading something), and the system would reboot again.
At the end, I gave up, and install OpenBSD-current on a virtual machine.