ATX Power Connector

[linlan]

I've got an Intel DP35DP motherboard and I'm a little confused about power connectors. The intel board has a 24 pin connector but it also has a separate 2x2 4 pin connector. The power supply I have (PowerUp 800W) has a 24 pin connector with the four pins detachable from the first 20. It also has two 6 pin +12V and 1 8 pin +12V but no separate 4 pin connector. I checked the specs on the Intel board and it says always use the 4 pin connector so I detached the 4 pin and plugged the 20 in the 24 pin connector and the 4 pin in the 4 pin.

When I boot up the system this way I don't get any response on video - not even a BIOS beep if I take out the memory. I get no video and no indication as to what's happening and the CPU fan doesn't spin up. I've checked the RAM and PCI-x video card in another system and they work fine there.

If I connect the 4 pin back to the 20 pin connector and plug both into the 24 pin connector on the board the CPU fan spins up but I still get no beeps (without RAM) or video (with RAM in)

Do I have to have a 4 pin and a 24 pin power connector and I just have an incompatible power supply? Thanks in advance for any help.

 

[knotknut]

If you look close you might find that your 8pin connector seperates making two 4 pin connectors.

 

[IH8U]

The 2x2 4-pin is for legacy P4 motherboards (also some cheap MB companies use it too)(most use the 8-pin). Though I have never heard of PowerUp. It sounds like it is a 20+4pin (the attached 4 pin is for the 24 pin). In other words use the 2x2 4-pin for the 4-pin, and the 20+4pin for the 24pin.

 

[jeremyrailton]

the four-pin connector you're talking about (the one in the top-left corner near the cpu) is for the CPU. I'm glad you didn't fry your board by plugging in the wrong plug. There definitely should be a 4-pin 12V plug for the CPU. See if the 8-pin plug will separate, or if one side of it will fit in the CPU plug. Don't force it in, if it doesn't fit, don't force it. if you don't have a 4-pin CPU plug at all, you can either do some creative wiring on your PSU or just buy another one.

Actually, I looked up the PSU and it says that it has that 4-pin plug. Turn on your x-ray vision to find it

 

[linlan]

Thanks to the people who suggested the 8 pin might come apart - it does into two 2x2. Still trying to figure out if I've fried the board. The CPU fan comes up a short period of time, then shuts down.

 

[knotknut]

CPU Fan thermal controlled. Spins up when system turned on, shuts down when drivers kick in. When the CPU reaches pre-determined tempature the fan will come on and the speed is adjusted to control the tempature. If fan never comes on under prolonged load then you have a problem.