Win11 22H2 Build 22621.819 ,issue with SSD write speed

Even the worst SSD in the world wouldn't reduce the performance that drastically at 75% full I would imagine..but then Advisers are supposed to be experts on all things computers whereas I am not so I defer to them.

Not sure this article is of any use but there are a few things you can check:

Obviously bear in mind that it is a 3rd party website so there may be ads (although my ad blocker isn't actively blocking anything)...and the 7th "trick" is trying to get you to buy one of their products. Still, Diskpart are reliable.

There's a couple more things in this article (as well as ones already mentioned):

That site definitely has ads and, again, some parts are clearly trying to sell you a product.

Beyond those, might be worth seeing if your SSD manufacturer has a disc management/troubleshooting program...for example, Samsung has Magician.

my SSD is new i just bought last feburary 2022 ,anyway i'll install another win11 22H2 on another SSD i have 500GB ,and see what is the results

I put my ssd 1 tb crusial bx to another pc with win 10 and make a crystal mark disk here is the results , so my problem is not the ssd ,its the new update of win 11 22h2, with Microsoft update it with a solution

now my windows 11 22h2 is fast now i don't know how ,after i unplug it from other pc and put it back in the laptop ,everything slow disapear ,here is the new result in the laptop :

can anyone tell me 1 correct reason ,how come it's fixed?

Its difficult to say for sure lol :)

Maybe there was a physical connection issue.

However, I noticed bad SSD drive performance on 22h2 also and they have a notice that there's a possible performance issue so that might be it or not:

"Copying large multiple gigabyte (GB) files might take longer than expected to finish on Windows 11, version 22H2. You are more likely to experience this issue copying files to Windows 11, version 22H2 from a network share via Server Message Block (SMB) but local file copy might also be affected.Windows devices used by consumers in their home or small offices are not likely to be affected by this issue."

"To mitigate this issue, you can use file copy tools that do not use cache manager (buffered I/O)."

eg https://support.microsoft.com/en-us/topic/november-8-2022-kb5019980-os-build-22621-819-b503e08b-b850-469a-8de9-74df8aebd5f4

You'll notice the wording can't completely rule out home users not being affected nor local file copy, etc. So again, it could have been it, or not.

There could also in theory be another Windows 11 22h2 bug for drive performance or one they haven't yet noticed.

There could also have been other things using your drive or heat throttling at the time or whatever.

The end result is really no one can specifically say for sure why you had seen poor disk performance.

SSD in Windows 11 is slower than Windows 10. I have RAID 0 2x 1TB 850Evo for games and Windows 10 have more stable transfer 700-1200 Mb/s but on Windows 11 22H2 i have more unstable transfers 300-1200 mb/s