Many beginner PC builders bought the wrong GPU & PSU combo, so they wonder whether they can use a 6-pin Power Supply cable into GPU’s 8-pin connector.
No! You can’t use a PSU 6-pin connector into a GPU’s 8-pin socket because both the cables (6-pin & 8-pin) carry different wattage. The 6-pin cable delivers up to 75W, whereas the 8-pin cable delivers 150W of power.
So, if you use a 6-pin PCIe cable for the 8-pin GPU, then the Graphics card won’t get the necessary power to run. Check the table below to understand which PCIe cable delivers how much wattage-
| Motherboard’s PCIe Slot | 6 Pin PCIe Cable | 8 Pin PCIe Cable | 12 Pin PCIe Cable |
| 75W | 75W | 150W | 600W |
Now, let’s understand why you can’t use 6 pin cable on eight pin GPU socket by taking an example.
Suppose you have an RTX 2060 Super GPU, which consumes 175W power and requires one 8-pin connector from PSU.
Now, if your PSU doesn’t have the 8-pin connector and if you use 6 pin connector cable instead of 8 pins, then the GPU will only get 75W power from the 6-pin cable & 75W power from the PCIe slot.
In combination, the RTX 2060 GPU will get (75W + 75W)= a total of 150W power, where the requirement is 175W. Most of the time, the GPU will not work; in some cases, if it works, then your GPU will not perform up to expectations.
If all these seem confusing to you, then don’t worry; by the end of this article, all your questions will be answered.
What Happens If You Use 6-Pin Cable in 8-Pin GPU?
As we already know, it is not good to use a 6pin PSU cable for eight pins GPU, and if you closely check the 6pin & 8 pins GPU connectors, you will notice that the only difference between both the connector is that the 8-pin cable has two extra ground pins.
Rather than the extra ground pins, both cables have three pins that carry 12V. Most of the time, if you use a 6-pin cable in 8 pin GPU, your GPU will not work.
But, because of the matching 12V cables, sometimes, if you use a 6-pin cable for an 8-pin GPU, then your graphics card can run. Let’s dive deeper into this by taking the example of the RTX 2060 GPU.
The RTX 2060 GPU needs 160W power & it requires one 8-pin cable from the PSU. But, if you use a 6-pin cable instead of 8 pins, then the GPU will get 75W from the 6-pin cable and 75W from the PCIe slot on the motherboard.
By combining (75W +75W)= 150W, power will be delivered to the RTX 2060 GPU, where the requirement is 160W. In this situation, your GPU will run until you put an extreme load on your GPU.
But doing this kind of stuff is not recommended because it can limit your graphics performance & also affect the lifespan of the graphics card.
Sometimes using the 6-pin PSU connector for GPU 8 pin can cause black screen issues, and sometimes it can cause system crashing issues.
6 Pin PSU Cable But GPU Need 8 Pin: Here’s What To Do?
If your PSU has a 6-pin cable and if your GPU needs an 8-pin connector, then in a situation like this, you can use a different type of Adapter available in the market.
Different adapters are available in the market; which one you need depends on many factors. Below, I mentioned all those factors-
6 Pin to 8 Pin Adapter
This is the safest option if your PSU doesn’t have an 8-pin connector for your GPU. Check out this Cable Matters two-pack 6-pin to 8-pin PCIe adapter power cable on Amazon.
By using this Adapter, you will suck more power from the 6-pin rail than it is necessarily designed to support, which is absolutely fine as long as your PSU is capable enough to supply the power that your GPU will require.
Other Adapters
Besides the 6-pin to 8-pin adapters, various other adapters are available in the market that can be used for GPUs in specific cases.
Some of those adapters include the Molex to PCIe adapters & SATA to PCIe adapters. Unfortunately, these adapters deliver different wattages; therefore, you must be careful before using these adapters.
The Molex to 8-pin adapter or SATA to 8-pin adapters can deliver power up to 54W. At the same time, the dual Molex to 8-pin adapters and dual SATA to 8-pin adapters can deliver power up to 108W.
Suppose you have an RTX 2070 GPU that consumes 175W power and requires one 6-pin & one 8-pin connector.
Now, if your PSU doesn’t have the 8-pin connectors, you can use a Molex to the 8-pin Adapter or SATA to the 8-pin Adapter.
If you use these adapters, then RTX 2070 will take 75W power from the motherboard’s PCIe slot, 75W power from one 6-pin cable, and 54W via adapters.
By combining all the wattage (75W +75W+ 54W)= 204W, power will be delivered, where the requirement for the GPU is only 175W. The GPU will work smoothly unless you do any overclocking.
You can read this entire article that I wrote about what you should do if your PSU doesn’t have enough pins for GPU.
Can You Use 6+2 Pins For 8 Pins GPU?
Yes! You can definitely use a 6+2 pins cable for the 8 pins GPU; in fact, the PSU 6+2 Pin cables are designed in a way so that you can install both types of GPUs a 6-pin GPU as well as an 8-pin GPU.
Modern Power Supplies from a reputed brand always come with 6+2 pin PCIe cables, so you won’t face any issues installing different GPUs.
The 6-pin PCIe cable would deliver power up to 75W, and if you attach the extra two pins with the 6-pin, then it would provide power up to 150W.
PSU Has 8 Pin Slot & GPU Has 6 Pin (What To Do?)
Many beginners are wondering if their Power Supply has an 8-pin connector, but their GPU only has a 6-pin port, so what should they do in a situation like this-
Most of the time, the PSU’s 8-pin cable will be split into (6+2) pins, so you can use the 6-pin and leave 2 pins.
But if your PSU doesn’t have this splitting 8-pin cable, then you can buy the 8-pin to dual 8 (6+2) pins adapters from Amazon. With the help of these adapters, you can easily connect a 6-pin GPU.
Pro Advice
Using different adapters can be complicated, especially if you are new to PC building; that’s why expert PC builders always recommend picking a compatible PSU with your GPU.
Before picking a power supply for your GPU, you have to check two things, whether the PSU can supply the required power for your GPU and whether the PSU comes with the necessary cables for GPU.
Check this complete guide about Power Supply & Graphics Card compatibility.
Wrapping Up
The gist of the discussion is that using 6 Pin PCIe cable for 8 pin GPU is unsafe, and instead of doing this, you can buy different types of 8-pin adapters available in the market.
This article clears all your doubts about using a 6-pin PSU connector on an eight-pin GPU. If you have any questions, then ask in the comment section.
thanks! very helpfull