This product was exact replacement for a faulty 3040 mini motherboard. Based on the diagnostic light pattern on the optiplex 3040, it suggested that the motherboard was faulty. Computer would boot up sometimes and as it was booting, it would go dark with a flashing orange light.
Ordered this replacement board and only had to remove some screws from the old motherboard, remove some cables and the WiFi card. Put the replacement into the unit which was a perfect fit. Reconnected everything and it has worked fine for better part of a week now. Took about 15 minutes start to finish and I had not replaced a motherboard before.