No, the M.2_2 socket does NOT support SATA drives. It ONLY supports PCIe NVME drives. The M.2_1 slot supports both SATA and PCIe NVME drives. However the M.2_1 slot ONLY supports SATA drives if you are using an Athlon CPU rather than a Ryzen CPU.
(M.2_1)
3rd/2nd/1st Gen AMD Ryzen™/ 2nd and 1st Gen AMD Ryzen™ with Radeon™ Vega Graphics :
1 x M.2 Socket 3, with M key, type 2242/2260/2280/22110 storage devices support (SATA & PCIE 3.0 x 4 mode)*2
AMD Athlon™ with Radeon™ Vega Graphics Processors :
1 x M.2 Socket 3, with M key, type 2242/2260/2280/22110 storage devices support (SATA mode)*2
3rd/2nd/1st Gen AMD Ryzen™/ 2nd and 1st Gen AMD Ryzen™ with Radeon™ Vega Graphics/ Athlon™ with Radeon™ Vega Graphics Processors :
2 x SATA 6Gb/s port(s)
Support Raid 0, 1, 10
(M.2_2)
AMD B450 chipset :
1 x M.2 Socket 3, with M Key, type 2242/2260/2280 storage devices support (PCIE 2.0 x4)*3
4 x SATA 6Gb/s port(s)
Support Raid 0, 1, 10
So, I don't think this problem necessarily has to do with the M.2 drives unless it only happens when there is a drive in the M.2_2 slot. It sounds more like memory training. Do you have D.O.C.P enabled in the BIOS? Do have fast boot in the MEMORY section enabled? Not in the boot section, but in the memory/RAM section.