You can plug a 4 pin 12 volt cable into an 8 pin EPS connector but there's no guarantee that it will work. If the motherboard expects only one 12 volt rail then a 4 pin 12 volt cable may work. If the motherboard expects two 12 volt rails (most dual CPU motherboards require one 12 volt rail per CPU) then it won't work. Even if the motherboard works with a 4 pin 12 volt cable, you are still only providing half of the current carrying capacity which would be provided by an 8 pin EPS cable. That can overheat both the motherboard connector and 4 pin cable. Scorched or melted connectors can be a result. A motherboard which has the 8 pin EPS connector expects a lot of current and you are taking a risk by plugging in a 4 pin cable. The 4 pin cable only fits at one end of the 8 pin EPS motherboard connector so you can't plug it in improperly. If you don't have an 8 pin EPS cable then you can use the adapter shown on the right. It converts a couple of 4 pin peripheral cables into an 8 pin EPS cable. If you use one of those then be sure to plug the 4 pin peripheral connectors into separate cables coming from the power supply. If you plug them both into the same power supply cable then you are drawing all the power of the EPS connector through a single 18 guage wire. You can often get away with that but there's no reason to do it. |