MemTest86 can not diagnose many types of PC failures. For example a faulty CPU or motherboard that causes Windows to crash will most likely just cause MemTest86 to crash in the same way.
Often the memory works in a different system or the vendor insists that it is good. In these cases the memory is not necessarily bad but is not able to operate reliably at high speed. Sometimes more conservative memory timings on the motherboard will correct these errors. In other cases the only option is to replace the memory with better quality, higher speed memory. Don't buy cheap memory and expect it to work reliably. On occasion "block move" test errors will occur even with name brand memory and a quality motherboard. These errors are legitimate and should be corrected.
MemTest86 supports all types of memory. In fact the test has no knowledge of the memory or CPU type nor does it need to. MemTest86 is able to test all types and brands of memory. If the information reported regarding chipsets or CPU's is incorrect it will not affect testing in any way. This not a problem or bug but is listed here due to the many questions about this issue.