A test adaptor board connects to a personal computer (PC) motherboard that tests a memory module in a test socket. A standard memory module socket is removed from a target DRAM module slot on the component side and the test adaptor board connects to the target DRAM module slot on the reverse (solder) side of the motherboard. The target DRAM module slot is a middle slot, such as the second or third of four DRAM module slots. The first and fourth DRAM module slots are populated with known good memory modules storing the BIOS at a high address and an operating system image and a test program at a low address. The test program accesses a memory module in the test socket to locate defects. The motherboard does not crash since the BIOS, OS image, and test program are not stored in the memory module under test.