I have Elitebook 840 g2, with 1TB Sata SSD 2.5 inch and windows 10 installed on lt.
Recently I bought "1TB NVMe PCIe M.2 2242" I installed it on my laptop as secondary disk " windows still on the old SSD.
the strange thing that once I installed the NVME the CPU temp became very high and after 10 minutes the NVME stop working, after switching off the laptop and wait for some time, its work again and after 10 minutes stop working again,
one more thing the "HP GNSS Sensor" and " HP Radio Manager Device "in the Device manager have yellow triangle.
I removed the NVMe disk, the CPU temp become cold again, but the "HP GNSS Sensor" and " HP Radio Manager Device "in the Device manager still have yellow triangle.
The NVMe is working fine in external USB case or in desktop motherboard !!!
are you really serious !!!! there is no point of using (SATA M.2 SSD) its limited to speed of (6Gbs) and expensive, better to use normal SATA SSD 2.5 inch will give same speed, binger capacity and cheaper ( 1TB cost 100$ only ).
NVMe much faster performance, the one I installed give ( 20Gbs ) speed (1TB cost 160$) in 2242 size
there is model give up to (35Gbs) but in 2280 size.
SATA M.2 SSD slow and more expensive now, because its rarely available now.
Elitebook 840 g2 is supporting NVme .
any way to answer your second question, Yes Within 10 mins, I can see and use it in File Explorer.
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