Hi @Sushieater  the Alienware m15 R1 Ports and connectors has Thunderbolt 3 (USB Type-C) which is capable of transmitting at a rate of 40 Gbps. Does Task Manager say your system is unusually busy, is an application using all the system's resources? 

OK. So I have two SSDs 1TB and 2TB. Both M.2 2280 NVMe.

I am transferring photos from the TB card reader to one of the internal SSDs.

Few months ago I saw speed as high as 1300MB/sec but it is a long transfer of many files so it eventually go down to more like 900MB/sec

But then I updated everything from Dell site and now speed is 625MB/sec of the same type of files. Exactly the same type actually.

The CFExpress cards I am using rated at 1730MB/sec

Thanks

Hi @Sushieater  thank you for sharing update.  What version of Windows 10 x64 is installed?

Intel Thunderbolt Controller Driver Version 17.4.79.510, A12 driver package supports only Windows 10, version 1909 (19H2) or earlier. It is not compatible with Windows 10, version 2004 (20H1) and later. 

Connect Thunderbolt card reader to laptop so that it is part of your system. Then click on Intel Driver & Support Assistant to identify your products and get driver and software updates for most of your Intel hardware. 

Windows 10 Update Assistant can be used to incrementally update window 10 versions to the current 21H1. The most recent window driver updates will then become available. 

Please click on Kudos to say thank you for response from user that is not employed by Dell. Please share an update on progress, so that other users derive benefit from your experience. Thank you. 

OS Name Microsoft Windows 10 Enterprise

Version 10.0.19042 Build 19042

That link could not find my TB so no drivers for it.

Hi @Sushieater  thank you fr sharing update. 

Please visit Device Manager and roll back Intel Thunderbolt Controller Driver to an earlier version, or visit Dell driver update and install the Older version that was installed before there was a Thunderbolt driver problem. 

I have tried that already but the speed remained the same. Thanks.

I tried that too, months ago. It has been 3 months since I noticed the problem.

Hi @Sushieater  thank you for sharing an update.

If Windows 10 Restore has been enabled on the OS(C:) boot drive, is it possible to go back to an earlier Restore Point, before the Dell updates were installed? 

Hi @Sushieater  than you for sharing update. 

Please see if Reliability Monitor has recorded an event fault during transfer date/time. 

Looking at 2 months history I only see dwm stopped working one time and firefox crashes a few times but that is it.

Hi @Sushieater  thank you for sharing update. 

Please run Windows 10 Check Disk to search for and fix any file errors on the OS(C:) boot drive. 

There is nothing wrong with the installation.