Except for servers, this is the first time I've purchased this class of workstation/desktop. Perhaps it's due to the generation but the P920 does some funky, maybe more along the lines of inconsistent things during bootup/restart. The system would take at least a 30 seconds to go through POST and while I never timed it my guess is a minute if CSM (legacy/UEFI compatibility) is enabled.
I noticed sometimes it beeps and sometimes it does not at bootup/restart. Maybe it's due to power unplug before power on.
Then sometimes it ramps the fan up for a second but sometimes it does not during a reboot.
The computer displays "Lenovo" during POST and it displays "To interrupt normal startup, press Enter" at the lower left. Depending on options selected in the BIOS this message remain at different timeouts. It would be nice if the message could reflect if Enter has been pressed because flakey keyboards could offer a false sense of confidence that the key was pressed. Dell's POST display shows this feedback.
I don't like these "quiet" boots and prefer messages display POST codes/descriptions along with any OPROM messages like what Supermicro does. Supermicro does both, providing a graphical logo with POST status on the bottom. The front bezel does have a POST code LED but if showing POST codes is turned on the display remains on until system is turned off. I just have it display error codes only. There are LEDs for the front USB ports and they are lit up while the system is on. I'm on the fence about these USB LEDs: it's nice when it's dark and I need to find the port. My computer room is quite dark/dim most of the time but an annoyance when I don't need to plug anything into USB. There is no LED for the card reader.
One more thing that happened to the system several days ago. As I am still transferring my data and setting things up, after "To interrupt normal startup, press Enter" disappears instead of booting to a boot device (storage, network), anything except BIOS, it would display "Error sending end of POST to ME!" on the upper left hand corner then boot loop. It was obvious something was corrupted but what to do to recover. Most folks on the internet, including Lenovo support suggests updating the BIOS but I couldn't do that without the ability to boot an OS. And the BIOS does not have a BIOS update feature like Dells do. I remember the last thing I did was to update the ME firmware around a week prior. Typically updating ME firmware should be done after updating to the latest BIOS. I remember the updater completed and then perhaps an hour or so later I saw the system update again then reboot. I thought nothing of it but noticed the BIOS showed Intel AMT was enabled but I couldn't disable it. Clearly something was not right and ME got some bad setting.
Out of desperation I looked for the CMOS clear jumper and bridged it to "clear settings" then powered up. It booted and sounded 2 quick beeps then repeats. Powered down and moved the jumper to "normal" position. It took much longer to boot, and that resolved the problem. The BIOS now allowed unconfiguring Intel AMT. A slight tangent, it's a shame Intel is having financial trouble as they have laid off their employees who created MeshCommander and MeshCentral so these tools are no longer developed. Their Github and NPM repos will still be maintained. While I never used MeshCentral, MeshCommander is the easiest way to manage Intel AMT-enabled systems.
The noise is probably a little louder than my Z620 but I'm facing the rear in its current "migration" position so it's not a good indicator. Besides it has two CPUs instead of one. Overall it's pretty quiet compared to my X11DPU. The X11DPU is not bad for a 1U server either when the BIOS is set correctly. I recall something about OS controlling fans then things ramp down quickly after OS/PXE boots.
