Question slow PCIE ssd write speed

[justajok3]

Adata XPG 8200 240 GB

Recently I used CrystalDiskMark to test my ssd speed but the result is not good
Sequential Read : 2.4GB/s
Sequential Write: 287.3 MB/s
This ssd is used as a C drive and 80% is used

Performance advertised
Sequential Read: 3.2GB/s
Sequential Write: 1.7GB/s
Anyone know why the writing speed is so slow?

 

[rgd1101]

is too full.
and what the full system spec?