Possible Motherboard and Power Supply Incompatibility

[tangykevin]

Hello.
I recently bought a Corsair CX650M (http://www.microcenter.com/product/460288/CX650M_650_Watt_80_Plus_Bronze_ATX_Modular_Power_Supply) from my local Microcenter and I am having trouble booting my PC with it.

NOTE, I exchanged PSU thinking it was DOA, but still the same problem occured

My PC Specs are:
Intel Q9400
M017G Dell OEM Motherboard, for reference (https://www.amazon.com/M017G-MOTHERBOARD-STUDIO-Mini-Tower-Systems/dp/B003F8MTDK)
6GB DDR2
Radeon HD 6450
350W Solid Gear TFX PSU

Before I continue, I transplanted this Dell OEM computer (Dell Studio Slim D540S) into a new case (Cooler Master N200) mainly for better airflow and future upgrade. Also, the case connectors are all working (audio, usb, front panel connectors).

When I first plugged in the Corsair PSU into the motherboard and booted it, it turned on and off and turned on again. In this time, the monitor didn't display anything. I tried resetting the CMOS (switching jumper caps and removing battery) and still nothing happened upon booting. When I used my old power supply, the computer booted and the screen was displaying Windows. I continued to diagnose the problem by using two power supplies in one motherboard. I plugged the 4pin CPU connector from the Corsair PSU and the 24pin connector from the old 350W PSU and magically, it worked. I am assuming there is something wrong with the 24pin connector from the Corsair PSU but when I jump-started the Corsair PSU (paperclip in green and black pin), it turned on. I am speculating that the 24pin connector from the Corsair PSU is not providing enough power to the motherboard but I have no idea how to test if the 24pin is providing suffice power. I am also speculating that I might need to replace the CMOS battery. I really don't know what's going on lol. Please help.

Thank you,
Kevin

 

[dontlistentome]

One thing occurs to me. In older systems, most of the power use was not in the 12V output as it is now and in the last few years. It could be that your system needs more power in the 3.3V and 5v outputs than the relatively newer ATX power supply provides. Look at the label on the original power supply and see how the output wattage is distributed.

Another possibility is that while Dell was using standard connectors on their power supply, maybe they are not wired in the standard way or providing standard levels of power. Just because it's a 24 pin connector doesn't mean it's doing the exact same thing as the Corsair 24 pin connector.