Could you post your system components.
Errors reported by MemTest86 it is usually related to bad memory modules but it could also be related to RAM incompatibility.
It could happen that a RAM module or kit might not be able to run reliably at full speed, so using a different speed profile (2933MHz) on the motherboard BIOS could fix these errors.
If you haven't, try updating the BIOS. Many times updating the BIOS could help with RAM issues.
In some cases the only option is to replace the RAM with better compatible modules.