I asked MikroTik Support and of course there is no drivers for windows 11 etc.. Just looking for something else as they do show up in Device manager. Any other suggestions?
The help site is clear:
The device is supported in Linux (minimum kernel 5.15.25) and RouterOS (minimum version 7.x), but > it will not be recognized in Windows> .
https://help.mikrotik.com/docs/display/UM/CCR2004-1G-2XS-PCIe#heading-OperatingSystemSupport
They show up as active in win10? If so what driver are they using?
AT YOUR OWN RISK:
https://www.ath-drivers.eu/download-driver-for-Atheros-chipset-with-id-50-and-Windows10-64bit.html
Yep just devices does not start 
On device details / properties / device instance path
what is the PCI\VEN_xxxx&DEV_xxxx&SUBSYS_xxxxxxxx&REV_xx etc. ?
Device PCI\VEN_1969&DEV_1083&SUBSYS_00000000&REV_00\4&1a972e93&0&0009 requires further installation.
I do not have a spare parts to test on win 10, but probably the string is emulated, not real… (win 10/11 is the same from this point of view)
ya, got me 
would be nice to have a link but happens
I do not have a spare parts to test on win 10, but probably the string is emulated, not real… (win 10/11 is the same from this point of view)
According to the block diagram, the Ethernet controllers exposed to the PCIe host are indeed not “real”. They are kind of emulated inside the AL32400 CPU, and seem to be compatible with the Atheros AR8151 PCIe Ethernet controller.
On Linux, the Atheros AR8151 driver is used for CCR2004 PCIe. It contains a patch from MikroTik specifically for CCR2004.
If the Atheros AR8151 Windows 10/11 drivers floating around the Internet are not able to bring the device up, there is not much left to do than hoping MT releases some working Windows drivers some day.
Out of interest:
Because the CCR2004-1G-2XS-PCIe takes some time to boot ROS, on Linux a rescan for PCI devices has to be initiated.
How is this done on Windows?
Mmmm… deleting the devices and “detect new hardware” right mouse menu? (i have win on Italian)
But for waht I know, windows do not support “hot swap” PCIe replacement…
Yep, and MT told me that they are not planning on putting out a driver currently. everyone tell them via support@mikrotik.com hehehe.
Shame but it is what it is.
But why would you want to use one of these with Windows ?
Because Windows has HYPER-V and allows building labs or even production environments with no side virtualization software. It is enough convenient.
Via boot delay. CCR2004-1G-2XS-PCIe is booting up for ~ 11 seconds so a boot delay of 15 seconds is enough.
BTW. It may be possible to use the device on Windows with HYPER-V and DDA. If you have a modern motherboard that supports SR-IOV, it is possible to dismount the AR8151 devices #2..#4 and passthrough them to a HYPER-V VM. Linux or FreeBDS inside the VM should work well with the passed devices. However, you won’t be able to dismount the first AR8151 - Windows detects it as an old-style PCI device and can’t configure it for PCIe proxy. Unfortunately, I can’t test this guess because only vT-x & vT-d isn’t enough but my MB doesn’t support SR-IOV.
If anybody can check this guess - it will be very good.
It has been a year does this work in Windows as confirmed?
Also the boot delay post was this confirmed?