Dell Latitude 5490 - Samsung PM981a NVMe SSD using 2x PCIe Lanes instead of 4

[Psychoticapex]

I have updated the NVME SSD: swapped a HP EX900 500GB (no DRAM) to a Samsung PM981a 512GB (with DRAM). I have benchmarked the Samsung SSD on a Lenovo laptop and got speeds around +3000MB/s.

 

On the Dell I get 1700MB/s and Crystal Disk Info shows "Negotiated transfer rate - PCIe 3.0 x2". The laptop is capable of PCIe 3.0 x4 as stated also "Highest Possible Transfer Rate - PCIe 3.0 x4".

 

Troubleshooting:

- Changed in BIOS from RAID to AHCI;

- Clean reinstall Windows 11 in both RAID and AHCI separately;

- Re-seated the SSD multiple times;

- BIOS is using the latest firmware;

- All drivers are up to date (checked with Dell Command Update, Dell Support Assist and on the website);

 

How can I make the SSD run at this full speed on this laptop? Has anyone encountered this before?

[Zagna]

The SSD is capable of PCIe 4x, laptop has it wired for only 2x.