I have a Samsung SSD EVO 850 256GB and I recently started noticing very slow write speeds.
I installed the latest version of Samsung Magician (7.2.1) and ran a Performance Benchmark on the drive (it was taking over 2 hours, so I canceled the test).
After this, I enabled "Full Performance Mode" on the drive (to enable RAPID), ran the test and it worked fine (5600 MB/s sequential write).
But after a few minutes I got the error "RAPID mode is not working as intended due to system internal errors. Please disable RAPID mode. Do you want to uninstall RAPID?"
My operating system is Windows 10.
Can you help me?