Business Notebooks

Hi, I have a problem with my HP ZBook 15v G5 (Mobile Workstation, 2018): sometimes, it unexpectedly automatically shuts down, without a proper disconnecting screen - it just goes black and won't turn on again for at least 10 minutes (but it can last up to 45 minutes).

Some other information about the PC: Intel Core i7-8750H, 16GB RAM, NVidia Quadro P600 4GB, 1TB SSD + 256 GB SSD, Windows 10 Pro 64-bit (updated regularly).

Some other information about the issue: it started around mid-May 2020. It used to happen only when the PC was under heavy load, fans at full speed, and I thought it could have been an overheating issue (still surprising, considering that I wasn't doing anything that I hadn't already done in the past months). Anyway, the problem persisted and has occurred also when the PC wasn't that hot, nor under heavy loads.

It happens both on battery and under charge, with Wi-Fi on and off, just to name a couple different situations that made no difference: the PC shut down and doesn't wake up for quite some time.

I also assumed it could be some kind of virus: I scanned the entire system without results, then did a factory reset (including the disks), then a clean installation of Windows, then another factory reset. The problem is still there.

Although it is more likely to happen when the CPU/GPU usage is high and temperatures arise, it also happened once when downloading a film from the Netflix Windows app (not really a heavy task) and twice when looking for some settings in the BIOS (again, not really a heavy task at all).

I recently cleaned the two fans and this keeps temperatures a bit lower, but still the PC shuts down.

Today I kept an eye on the temperatures with SpeedFan software, while rendering a scene in a 3D software (heavy load, 100% CPU usage): moments before shutting down, GPU was 62°C and CPU cores ranged from 73°C to 81°C.

Every time this issue happens, when I finally restart my computer I get a black screen with the following text:

"The CMOS checksum is invalid. The CMOS will be reset to the default configuration and will be rebooted. Please check your BIOS Setup options to see if they change.

CMOS Reset (502)

ENTER - Reboot the system".

After rebooting, in the Windows Event Viewer I get a Kernel-Power critical error (ID event 41; Activity category 63).

Last piece of information: both the PC and its charger never fell down on the floor, nor got hit by anything: they are both physically intact.

Can somebody help me?