4-Pin ATX on 8-PIN ATX mobo

[Olosen113]

Hello! I want to upgrade my rig by buying a new mobo(Gigabyte B250M D2V ), ram and cpu.
The problem is that my old mobo(gigabyte ga-g31m-es2l) only had 1 4-pin ATX 12V same as the PSU provided, only 1 such cable. The cpu I was using was a q6700 that ran just fine. My question is, can I use only 1 4-PIN ATX 12V from the PSU to power the new cpu(I5 7400 3Ghz)?

 

[anbu13]

Give it a try by connecting the 4 Pin ATX into the four pin connector that matches with it. If the CPU requires more power it won't power on the CPU with the 4 Pin ATX 12V then you have to go for a PSU with 8 Pin ATX 12V. 4 Pin to 8 Pin converters are there, but choose a good quality one if you're going with it rather than the PSU.

 

[Olosen113]

Give it a try by connecting the 4 Pin ATX into the four pin connector that matches with it. If the CPU requires more power it won't power on the CPU with the 4 Pin ATX 12V then you have to go for a PSU with 8 Pin ATX 12V. 4 Pin to 8 Pin converters are there, but choose a good quality one if you're going with it rather than the PSU.

But, the 8 pin requires 2x4 12V, does that mean it needs 24V? or only 12 are good to go giving the fact that now im using a q6700 that uses way more power that the i5 7400.

 

[BFG-9000]

Each yellow wire can deliver 10A so that 4-pin is good to 240w, and an I5 7400 is only rated 65w. Just plug it in and give it a try.

More wires in parallel means more Amps, not more Volts, so your GPU with two 6-pin PCIe connectors is not running 72v.

 

[anbu13]

8 pin requires 2x4 12V, does that mean it needs 24V?

Imagine this 2 (2x 4 pins) separate 12V wires from a single 12V source(PSU) so its only 12V. Each pin used in those connectors can only carry 5 or 6 amps of current before it overheats, so adding in 4 extra pins (two more +12v and two grounds) enables another 10~12A of current to be delivered.

If you are Overclocking your CPU, it requires more power. If not overclocking a single 4 pin ATX 12V is enough to turn on your CPU. Good Luck.

 

[BFG-9000]

Neither I5 7400 nor B250 chipset can overclock. It's 65w period.

 

[Olosen113]

Neither I5 7400 nor B250 chipset can overclock. It's 65w period.

So, tehnically I'm ok with 7400 on one 4 pin?

 

[BFG-9000]

It would be fine being powered by a single pair of wires (a 2-pin), but some motherboards may refuse to power-on unless an actual 8-pin is used. In that case consider the adapter mentioned by anbu13 to trick the board into thinking an 8-pin is attached, or a new PSU. But try it first with just the 4-pin.

Your old Q6700 mildly overclocked would've used about 135w @ 3.33GHz and the I5 is less than half that.