A graphics card is one of the most powerful hardware in a PC and takes a considerable amount of power from the PSU. So, is it possible to use a second PSU for the graphics card?
Having an additional PSU for the GPU is possible. But how to make it work seamlessly with your existing PC setup? Let us explore the possibilities of using an additional PSU for the GPU separately and its benefits.
Can I use a Second Power Supply for Graphics Card?
Yes, Technically you can connect the graphics card to a second PSU, and it will work very well. This kind of setup is widely found with crypto miners and there are accessories available for this setup to work. With the help of a PSU adapter board with 24 pins and 4 Pin Molex connector, you can connect a second PSU to your existing PC.
Let us now understand how to set up a second PSU for your dedicated GPU to work seamlessly with your existing PC.
Requirements to set up a second PSU for your graphics card
For this setup to work, you will need a modular PSU with your existing PC. Because you should be able to connect Molex cables to the PSU. Here are the accessories and cables required for this setup to work.
- PSU adapter board with 24-pin and 4-pin Molex Connector
- 4-pin Molex Cable
- 24-Pin PSU cable
- Second PSU
- If you look at the PSU adapter board, you can find two sets of female pins. One is the bigger 24-pin Molex and the smaller 4-pin Molex.
- First, turn off your PC and unplug it from the power supply.
- Remove the panel to locate the PSU.
- The modular PSU in the PC will have pins to connect an additional 4-pin Molex cable.
- Take the 4-pin Molex cable and connect it to the PSU in your existing PC.
- Take the other end of the 4-pin cable and connect it to the adapter board.
- Then take the 24-pin PSU cable and connect it to the adapter board.
- Connect the other end of the 24-pin cable to the second PSU.
- Now we have connected the second PSU to the existing PSU.
- Power the graphics card using the second PSU and connect the GPU output to the motherboard in your PC.
- That’s it! You have now connected the GPU separately to a second PSU and have connected this PSU to your existing PC.
How does this setup work?
The PSU adapter board works similarly to a trigger sensor. When you power on your existing PSU, it will trigger the second PSU through the 4-pin Molex connectivity.
So, the second PSU will also initiate and power on along with the existing power supply. This will run the connected GPU too since you have connected it to the second PSU and the motherboard.
The GPU runs seamlessly without any need for separate powering on and you can start using the GPU as usual.
What to check before selecting the power supply?
Generally, it is not advised to use a separate PSU just for powering up your graphics card. Because it is not worth it and there will not be any significant performance improvement. It is better to change the power supply unit entirely to a higher capacity that can support all your hardware properly.
But in some cases, you may be using a prebuilt PC that has a very small PSU. This cannot handle bigger GPUs and you cannot use them. Therefore, in such cases, you will need a separate PSU.
Since you are going to connect only the GPU and probably some small accessories to it, you just have to consider the wattage requirement of the GPU.
For example, a 500W PSU will be more than enough to power your GPU as well as an entire PC. So, you don’t have to worry more about the wattage.
But you must choose to buy a modular PSU which can come in handy to plug in only the necessary cables to the power supply. In a non-modular PSU, all the cables are fixed to the unit, and you cannot remove anything.
Therefore, try to buy a modular PSU with the appropriate power rating that can handle the GPU comfortably. Apart from this, you can look for efficiency ratings for better performance.
Why do we need a second power supply for a graphics card?
Most of the use cases in PC don’t require a second graphics card. You must try to upgrade the existing PSU to a higher capacity that can support your GPU appropriately.
Because having a single PSU for your PC can provide a better performance and proper power supply to all the hardware. If you get a PSU with proper wattage, it will be more than sufficient to power your GPU as well as other hardware.
Using an additional PSU just for a graphics card will consume a lot of power and has very less efficiency. It will not have any significant improvement in the performance and there are other disadvantages too.
For example, you cannot conceal the second PSU in your existing case. You have to leave the side panel of the PC case open for the cables to reach the first PSU and connect it to the second one. Likewise, there are practical difficulties and issues with this type of setup.
This will not bring any benefit unless you have a dire need for it. If you are using a prebuilt PC, you can try to make this setup. But in that case, too, you will not have a modular PSU in the PC and you cannot set it up without professional help.
Therefore, a second power supply is not necessarily needed to connect a graphics card unless your current PC is prebuilt.
Although it may be possible to set up a second PSU for your graphics card, it is best to upgrade the existing one to support your GPU. But if you have a special need for this kind of setup, then you can follow this guideline and set up a second PSU for your graphics card.