I have one of these motherboards too and
was sucked in due to an inaccuracy in all reviews I have seen of this motherboard, including
this one. In particular having three M.2 PCIe v4.0 x4 slots. As someone that uses 4x M.2 drives in his X399-based 1st-gen threadripper system I was excited to see that I could move my M.2 drive set over to the X570-Ryzen 3950X with no loss of drive performance...
Wrong!!!
Look closely at the user manual that comes with these boards and you will find the 3rd M.2. (PCIE_M2C) slot and you will see it only supports up to
M.2 PCIe v4.0 x2.
This unfortunately is an inaccuracy shared across many reviews of motherboards having a x570/3rd gen Ryzen configuration. You would think that this would be one of the first things caught in reviews of this chipset + processor combo.
At least there will be only one drive I have top accept this drop in performance since the PCIE x4 slot is usable for the 4th M.2's adapter card. Good thing I only run a few SATA HDD & SSD drives.
@slidai Yes you can use the M.2 slots without heatsinks. Beware the closeness of the M.2 C slot though - it is pretty close to the CPU socket and might interfere with some CPU cooling solutions (I have an AM4 +TR4 compatible water block that won't fit because of it).
On Motherboard quality... A $300+ USD that doesn't have a diagnostic LED readout or reset/on-off buttons onboard? Seriously? Jeez!