So after googling i see A LOT of people with the same problem.
I've got a Seagate Firecuda 520 NVME 2TB Drive (On a MSI MPG X570 Gaming PRO CARBON WiFi) that's supposed to have read/write speeds of 5000 MB/s / 4400 MB/s.
It worked just fine in the beginning but as of late i've been experiencing problems. I can't get write speeds over ~1 GB/s on the drive.
Tried drivers from different vendors
Updated chipset drivers
Changed M.2 Slot on the motherboard
Confirmed it's running on PCI-E Gen 4.0 X4
Swapped in another Seagate Firecuda 520 2TB and i've got the same issue
Disabled/enabled write caching
Read speed sits steadily at 5000 MB/s so the port is working correctly.
My other drive a MP510 PCI-E Gen 3 works fine and gives me +3000 MB/s write speeds.
The new AMD chipset drivers ( 1.8.19.0915 ) fixed the write speed issue.
Write went from 1,000 MB/s to ~4,700 MB/s.)
Unfortunately i've tried a plethora of different drivers with the same result.
Anyone got any ideas on how to solve this? I've tried everything i've found on Google.