Hi, @eikira Not clear which version you bought but I went with this one for the on-board wifi, the full-length 3rd pcie slot, and the option to put 4 m.2's in... though I'm only using 2 right now to avoid bandwidth sharing:

https://rog.asus.com/us/motherboards/rog-strix/rog-strix-z590-e-gaming-wifi-model/

I installed Win10 64-bit Pro in an Asus z590 and had no issues booting off a 500gb m.2 in slot #1 (closest to the cpu). I put my 2nd 2tb m.2 into slot #3 (furthest from the cpu, closest to the rear) because it wasn't clear from the docs if using the #2 slot would impact bandwidth. No csm or boot issues with this setup. Just make sure you reflash everything and update your bios from the Asus support page for the motherboard version you have. If photos of my bios settings help, be glad to oblige.

Only issue I had was something installed an app that collided with Vegas video memory. Unfortunately, I got so ticked off about it that I starting un-installing bloatware right and left and am not sure which one was the culprit or which thing installed it... my suspicion is that it was an audio recording app that hitched a ride along with the Realtek drivers. If you run into that issue, post a screen shot of your Win10 apps screen and I'll probably know it when I see it.

Also having an issue with hot-plug sata not being recognized by WIn10 immediately after reboot. But if I boot while a sata ssd is in a slot marked hot-plug in the bios, then unplug it even though Win10 says it's in use, then suddenly hot-plug starts working. Probably need another bios or Win10 update to fix that.

@MMiles Asus can lick my backside till the sun will go supernova. they insisted in the email every manufacturer has exactly the same problem... which sounds stupid, since i talked with intel an hour ago and they told me, it is a mainboard producers choice.

@Howard-Vigorita read my issue again. CSM enabled = all drives show up, NVMe, SATA SSD, HDD, DVD/BR, but iGPU of 11900k simply not selectable anymore.

CSM disabled = no drive is there, no USB Stick no SSD SATA, no DVD Drive, no NVMe.

I have ASUS ROG Strix Z590-A gaming wifi.

Are you running the BIOS that came with the motherboard? I know that some of the latest ASUS bios are terrible and if there is an earlier version you might want to try flashing it. Check out the ROG forums and type in the BIOS version you have.

You probably already did this but you might want to make sure that you have the latest Intel chipset drivers as well as the MEI.

The installation process is always the same. First the BIOS, then the chip set, then the management engine drivers, then the rest.

When downloading the ASUS drivers, there is a clear distinction between the chipset drivers and the management engine drivers.

@MMiles i run bios flash to newest first pretty much always on new mainboards.

It is just annoying, you pay premium prices to NOT be limited and than you have just annoying more work to maybe figure out their silly ways of doing pseudo security stuff...

@Howard-Vigorita did you connect your display or one of your display through the internal DP/HDMI port?

@eikira when I first powered on I used the onboard hdmi. Never touched csm... just looked and it's set to disabled. Took a while to decide which video board to borrow from another system. When I put one in I had to make a change to use pcie_graphics while keeping cpu graphics available as a 2nd display. Apparently if you don't set it for dual display, it disables the igpu and it doesn't show up for gpu-z or Vegas. I vaguely remember seeing a warning that using dual graphics disables csm. I think it took a couple trips into the bios to get all the graphics options to show up. I'll post a few snapshots...

Btw, if you haven't installed the os yet, I had to go into "boot over-ride" shown above to allow boot from the usb bluray device I used.

@eikira

Btw, if you haven't installed the os yet, I had to go into "boot over-ride" shown above to allow boot from the usb bluray device I used.

That is the issue i cant override anything because if iGPU is enabled (means CSM is disabled) there is no device to boot from shown. I have now a AsRock mainboard, at least it booted from an USB port and i could install Windows, but its more or less even here the same issue, with iGPU-CSM... i dont know what they are thinking. I am already wondering what will happen if later i plug back one display to the discrete gpu instead of the MB DisplayPort...

So the AsRock MB at least allowed and booted from USB and DVD Rom to be able to install a new OS. Asus just did not care. A absolute useless mainboard if you want Intel iGPU... for CPU only i did not need that Intel, i have an AMD 5950x. No thanks Asus go away.