Is the 8-pin necessary for i5-750? Can 4-pin handle it?

[dctokyo]

lol, and how can he do that precisely?
The 8pin IS NOT NEEDED! But just is better for some overclocking because it can offer more power to the motherboard.

I mean he should get a PSU that has 8 pins for the CPU, have you seen the latest EVGA boards? dual 8 pins these days.

also they sell 4 pin to 8 pin adapters,

Does the manual say that a 4 pin can be connected instead of 8 pin I wonder?

You can plug a 4 pin 12 volt power cable into an 8 pin EPS motherboard 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 (many 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 serious 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. That is, it only fits into one end of the motherboard connector unless you force it. If the cable doesn't go into the socket easily then you're probably trying to plug it into the wrong end. But then again, it's not a good idea to try to run with a 4 pin cable in an 8 pin motherboard anyway.