>> Nieko aš neišspausiu - pralaidumas tas pats, ar x2, ar x4, bent jau taip
>> SiSoft rodo, pridedu screen shot.
>
> ne taip supranti.. butu nelogiska.. vienos PCIe 3.0 linijos pralaidumas yra 8Gbps..
> kai naudoja 2lanes - 2*8000/8/130*128 = ~1969MB/s, kai 4lanes - ~3938MB/s
> https://en.wikipedia.org/wiki/PCI_Express#History_and_revisions

PS. 
https://h30434.www3.hp.com/t5/Notebook-Hardware-and-Upgrade-Questions/HP-Probook-450-G5-2rs03ea-M2-slot-availability/m-p/6645414/highlight/true#M451549

You must notice that the M.2 slot in 450 g5 is nvme pcie gen3 x2. So if you have an ssd
like nvme pcie gen3 x4 which are fastest one in the market, it will work with the half speed.