Do you have the authority to connect a PCIe power connector directly to the CPU?
Do you have the authority to connect a PCIe power connector directly to the CPU?
So my latest MSI power supply arrived damaged. I have all the components for my new computer except the PSU, and I need to assemble it immediately.
I own an older power supply with just one CPU connector, but my motherboard needs two. Can I use one of those connectors on the PCIe rails to power the CPU? They match in size and voltage (12V measured on both sides). The PCIe rail can handle more current.
Should that work?
I possess an outdated power supply with just a single CPU connector. The motherboard needs two connectors. Can I utilize one of the PCIe rails to supply power to the CPU? When sharing a troubleshooting thread, it's standard to provide complete system specifications. Please format them as follows:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
Include the PSU age along with its make and model.
I created a shortcut between the 4th pin and ground (green and black).
Even if the paperclip test made it functional, it doesn't show the actual power capacity for your components.
Moved the thread to the Systems section from the Motherboards section. Please keep it focused unless you need complex solutions.
The test only confirms that the PSU has some power, which doesn't matter.
For the first question, the answer is no—PCIe connectors or cables aren't suitable for CPU auxiliary power.
If both PSUs are semi-modular, you must use the provided cables; trying alternatives could damage everything.
This one?
https://antec.com/product/power/hcg-gold750
If it is, you must have lost or missed getting two 8(4+4) Pin EPS 12V cables that came with it. Perhaps you can look to buy some for it but I wouldn't bother about a 12-year-old PSU.
MB?
https://www.gigabyte.com/Motherboard/X67...v-10/sp#sp
You should be able to manage without those EPS cables unless you're overclocking and/or have many devices drawing a lot of power. Have you tried it?
When you mention "two connectors" referring to the ATX12V headers on your motherboard, it could be either four 4-pin connectors, one 8-pin and one 4-pin, or two 8-pin connectors. The diagram you referenced displays a mix of these configurations.
I've been using an older motherboard with an 8-pin ATX12V header while connecting it to a PSU that only provides a 4-pin cable for several years. Although this setup isn't the most efficient, it works for me. Reducing the number of +12V wires by half would cut the available current in half and increase the ripple voltage on the CPU VRMs. However, since I'm using a low-power CPU and have experience with electrical safety in my engineering role, I feel confident with this approach.
In situations where your PSU offers an 8-pin ATV12V cable and your motherboard requires another 4-pin ATX12V connector (as shown in the image), you typically don't need more than one 8-pin cable—unless the BIOS verifies the presence of both types. As long as you don’t overclock your CPU, a single 8-way cable should suffice until your new power supply is installed.
Connecting more +12V wires in parallel to the CPU VRMs increases the current capacity. If the PSU uses 18 AWG wires and each is rated for 7A, an 8-pin ATX12V cable can deliver up to 28A at 12V, which is more than sufficient for most CPUs—except for heavily overclocked models like the i9-14900K. In such cases, you may need additional 4-pin or 8-pin cables.
Having only a single 4-pin ATX12V cable provides 2 x 7A = 14A at 12V, which is adequate for low-power CPUs without overloading the 18 AWG wires.
there are two connectors with eight pins each, as illustrated in the top left corner.
I will attempt this until my new PSU arrives.
I plan to reduce the CPU frequency in BIOS so it never operates at full capacity.
I discovered what caused the issue with the PSU I received. It was purchased from Amazon, and the packaging looked somewhat worn out. Inside, at the very bottom, I noticed two metal tabs—not typically included in a plastic bag today. I assumed they were accessories for the PSU. Later, I realized there are such metal tabs on the back of the PC case that need to be broken during installation of a new component (like a video card).
Therefore, the PSU arrived used or damaged from Amazon.
The seller appears to be Amazon itself.
It seems they likely received an unopened return or one of their staff replaced a faulty unit with a broken one.