Hello my friends,
I know, that a lot of us had some troubles with Dell Inspiron 7577. We had mouse stutters, freezes, sound problems and slow Toshiba NVMe write speed.
I can confirm, that latest Insider Preview build of Windows 10 1803, RS5 17643, fixed all issues completely.
I no longer have mouse stutter, when clicking "Display Settings", OS seems a lot smoother. Other people confirmed that too on Windows forums using different laptops with GTX 1060 and Optimus technology. You just need to use RS5 17643 and latest Intel and nVidia drivers, that's all.
Latest Firmware to Toshiba XG5 NVMe finally fixed write speed issues, and everything is as advertised now. I want to say, that this only works in RS5 17643 and RAID On mode, Intel RST drivers. If you will try to use AHCI mode, write speed will be limited to 350+ MB/s. I tested that.
I don't know, when RS5 17643 will hit regular users, but I think in 2-3 weeks time. So if you have problems, just wait.
Thank you for posting this helpful post to the forum. Hopefully, it will also help other users as well.
Official Dell Support Statement Regarding the Bug
"The root cause has been identified as an issue being caused due to “Windows 10 display Cache issue” Microsoft is releasing a hotfix soon which should resolve the issue. We're checking internally with our engineers to see if the release is already out to share it with you. You can also check on Microsoft's website."
So, thank you Dell, for looking into this. This will help all laptops users, who has Optimus technology. As I understand, hotfix will be released for older Windows 10 versions too.
I saw your post the other night and it gave me hope for my crappy Toshiba XG5 writes speeds. So I tried updating to Win 10 Insider Build RS5 17650. After this update, I actually got ~1060 MB/s seq write in Crystal Disk Mark once after first boot, but then speeds went back ~350 Mb/s and fluctuated randomly. After I did a restart, this insider build crashed on me and got corrupted so I couldn't even start windows.
Therefore, I had to do a Win 10 system restore using the USB recovery stick I made using the dell software when I first got my computer. I ran Crystal Disk Mark 20 times and 17 times got ~2800 MB/s seq read and ~1070 MB/s seq write. Oddly, 3 times i got around 350MB/s so I don't know if it's the Crystal Disk Mark 6 software, Windows, or hardware related (maybe how power is managed?) This was in RAID mode and I did not try AHCI.
So, I'm thinking after you update to the latest firmware AADA4104, maybe you also need to do a clean windows install.
My system is XPS 13 9370 with Toshiba XG5 KXG50ZNV256.
P.S. I tried getting a replacement Samsung but was told to call a different support number
I think the issue might be caused if BitLocker encryption is enabled. I got good results by disabling it.