She doesn't have a 24-pin power port. It uses an 8-pin and a 4-pin CPU power connection.
She doesn't have a 24-pin power port. It uses an 8-pin and a 4-pin CPU power connection.
I recently chose to replace a preassembled system with an i7-4770 CPU, swapping it for a RTX 2060 SUPER graphics card and upgrading the power supply to a Thermaltake SMART 600 80 PLUS. Concern (the issue is clearer): My motherboard is a Dell Optiplex E 93839. It features an 8-pin connector that I can create using two of the four-pin connectors from the PSU—this works perfectly. However, the CPU power connector is a 4-pin, and I’ve already used all four connectors for the 8-pin setup. Fortunately, there’s a 24-pin connector that supports 20+4 pins, making it easy to detach the 4-pin and use it. The challenge is whether I can manage this setup. I have a 6+2 pin power supply for my 8-pin GPU. The second image shows the 4-pin connector beside the cooler. In the third image, near the left edge of the board, you’ll see the 8-pin connector for component power.
They’re built for a specific setup and can’t be easily changed. A lot of components are unique to Dell, and the motherboard isn’t ATX, so the connectors work differently. The CPU is often locked by Dell to stop upgrades, even if the chipset lets you. It’s usually smarter to use affordable parts instead of risking damage.
You cannot use the 4-pin connector from the 20+4 to power the CPU. The 4-pin CPU connector includes two GND and two 12V wires. The 20+4 version has one 12V, one 3.3V, one 5V, and GND connections. Inserting it incorrectly could short the 12V to ground or another voltage, risking damage to the power supply. Look for adapters that convert your 8+4 to 24+4 or use a 4-pin CPU connector compatible with EPS 8 pins or ATX power. You might also examine the pin layout of the custom connector and cut an old PSU cable, connecting it to your new power source. A multimeter could help verify the connections, and the circuit board documentation may clarify each wire's function (e.g., power supply stand by, PSON, power on, etc.).
You'll need to design your own cable connections for the new power supply unit. It's not as straightforward as removing four pins from a 20-pin connector, especially if they don't match up electrically. You'll have to locate the motherboard's wiring diagram to see the voltage each pin requires, and the PSU's wiring diagram as well. Then you'll have to solder each wire carefully. After assembly, use a multimeter to test each connection—mistakes could damage the entire system. If you're not comfortable with electronics, consider looking for an adapter online or replacing the motherboard altogether.
The 24-pin connector is a 20+4 design, and the maker mentions that the 4-pin section can be removed.
They suggested inserting the 20 pin as well. I assumed you wanted to use the 4-pin from the 24 pin for powering the CPU.
Yes, the 4-pin connector on the 20+4 differs from your motherboard's pinout. The hole shapes are likely distinct, making a secure connection difficult. This pin can be removed to adapt the power supply for older systems using the ATX 20-pin connector (such as Pentium 2 and Pentium 3 models). Adding this pin introduces a 12V wire, increasing the total to two wires—useful since modern setups rely on 12V for fans and PCIe slots. Previous boards often used 5V, with the 20-pin section containing multiple 5V and ground wires.
I have never tried to fit a optiplex mobo in a ATX case. So I wouldn't know. The reason I mentioned the cpu thing is cause in the end it's likely going to bottle neck even if you were to get it working, and that there is not upgrade path.
I apologize for the lack of clarity. The motherboard has an 8-pin connector and a 4-pin CPU power connector, similar to the images. I planned to connect both 4-pin connectors together as an 8-pin, but since I don’t have to force them in, they fit easily as intended. I would remove the 4-pin from the 24-pin connector and use it for CPU power.