GPU Power Connectors Explained

All the GPU power connectors may be difficult to understand. Here's a simple explanation of the 6-pin and 8-pin connectors and how they are different.

An often overlooked yet critical factor when building a PC is power consumption. A top-of-the-line graphics card can place too great a burden on many PSUs, and that is something gamers need to avoid. We have prepared this guide to help you better understand GPU power connectors.

Some low-end and mid-range graphics cards can only use the PCI Express x16 slot as a power source, but more demanding cards will need to use 6-pin or 8-pin PCI Express power connectors.

This can be particularly confusing when using a multi-GPU setup, as with the SLI. In that case, the power requirement is the sum of two (or more) connected graphics cards.

Let’s get started!

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PCI Express x16 Connector

PCIe Express x16 Connector - GPU Connector

Motherboards come with the aforementioned PCI Express x16 slot that can provide a maximum of 75 watts of power. Some feature multiple PCI Express x16 slots in order to connect more GPUs, but, as previously mentioned, this increases the power requirement.

Here are a few examples of GPUs that don’t require external power: GT 1030, GTX 1050 2GB variant, RX 550, RX 460, and many others. As none of these GPUs have a lot of processing power, they don’t need more than 75 watts of power.

6-Pin Connector

PCI Express x16 - 6 Pin Connector
A 6-pin connector

This connector can provide the GPU with an extra 75 units of energy. This means the graphics card will utilize the PCI Express x16 slot and draw power directly from the PSU (Power Supply Unit).

Related:What Power Supply Do I Have?

Despite the fact that 150 watts are enough for most graphics cards, high-end cards such as NVIDIA’s RTX 3080 require more than 320 watts and system power of 750 watts. As 150 watts will be enough for most mid-range cards, these usually feature the 6-pin power connector.

The terms “PCI Express cables” or “PEG cables” (for PCI Express Graphics) can also be used to describe 6-pin connectors.

8-Pin Connector

8-Pin Connector
An 8-pin connector

Although the math might not seem right when compared to the 6-pin connector, the 8-pin connector can deliver 150 watts to a graphics card. If the GPU requires more than 150 watts, it will come with an 8-pin connector or two 6-pin connectors.

As always, there are exceptions. The most power-hungry graphics cards come with a 6-pin and an 8-pin connector. For example, NVIDIA’s GeForce RTX 3060 has both types of connectors. As a result, it has a maximum power consumption of 170 watts.

There are even some exceptional cases where the GPU will have two 8-pin connectors. By adding the numbers together, we get a total of 375 watts, which is an extreme amount. In addition, you still need to power the CPU (another big energy consumer) and the rest of your PC’s components.

In even rarer cases, enthusiast GPUs require three 8-pin connectors. These are usually the manufacturers’ highest-end models made to provide the best possible cooling and overclocking. An example of such a GPU is the GeForce RTX 2080 Ti LIGHTNING Z.

In any circumstance, it’s definite that your device will have sufficient power with a dependable 650 watts PSU. However, if you’re building a gaming setup with an RTX 3080/3090 or wish to be ready for the future (which is nearly impossible), you should choose a more robust PSU. Take caution as heightened power brings a higher likelihood of excessive heat.

There is also a rule of thumb that the PSU runs best when it’s at 50% capacity, but that is a different topic that should be looked at on a case-by-case basis.

12-Pin Connectors

12 pin connector

With the release of NVIDIA’s RTX 3000 series, we were introduced to 12-pin power connectors. This move was made out of necessity as NVIDIA desperately needed the extra power for their most powerful cards and came up with a rather elegant solution.

A 12-pin connector is approximately the same size as an 8-pin connector, but it can consume a significant amount more power. NVIDIA was transparent regarding the availability of PSUs with 12-pin connectors, so it unveiled an adapter that enables two 6-pin connectors to interface with its card’s 12-pin slot.

Adapters Or Converters For Connectors

There are often compatibility issues when building a PC, and power connectors are no different. Fortunately, computers are made by engineers who like to modify hardware that isn’t suited to their needs by default.

A company called Molex pioneered these pin connectors all the way back in the late 50s and early 60s, and it has since become synonymous with the term. Don’t be surprised if you hear these being referred to as Molex Adapters or Molex Converters.

4-Pin Molex to 6-Pin PCI-E Adapter Cable

You must utilize this cable if your graphics card needs a 6-pin power connector, but your PSU does not possess it. Generally, it indicates an extremely old PSU, suggesting it may be time for an upgrade. If you insist on retaining your current PSU, note that this type of adapter occasionally necessitates one 4-pin connector, but it is usually two, which is advised.

4-Pin Molex to 8-Pin PCI-E Power Adapter Cable

This cable uses a double 4-pin connections and adjusts them to an 8-pin connection. 4-pin to 8-pin is something that will probably be handy with advanced graphics cards.

6-Pin to 8-Pin PCI-E Adapter Cable

If you’ve recently purchased a top-class GPU, it will likely require an 8-pin connector, which some PSUs might not have. In that case, the 6-pin to 8-pin adapter is your solution.

2x 8-Pin To 12-Pin PCI-E Adapter Cable

As mentioned earlier, the 12-pin power connector is the latest technology necessary for NVIDIA’s 3000 series graphics cards. Because there were relatively few PSUs with a 12-pin power connector on the launch of the 3000 series, NVIDIA included a dual 8-pin to 12-pin adapter with its product.

SATA to 6-Pin PCI-E Adapter Cable

This cable converts your SATA connectors to a 6-pin connector, but this is generally advised against. There is a chance that SATA won’t be able to handle the power that your graphics card requires, and this is not something that you want to encounter, especially if the cable is labeled as “SATA only“.

SATA to 8-Pin PCI-E Adapter Cable

SATA can also be modified for an 8-pin power connector. In this situation, there will be two SATA ports for one 8-pin connector.

Important Note About Adapters

In most cases, it’s best to upgrade your PSU if you lack connectors, as older PSUs weren’t built with current power requirements in mind. If possible, it’s best to use Molex to Molex for your GPU needs, as they have thicker wires and can transfer more current. A SATA to Molex adapter could be exposed and lead to burnout if the GPU draws more power with a higher load or by overclocking.

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Aleksandar Cosic

Alex is a Computer Science student and a former game designer. That has enabled him to develop skills in critical thinking and fair analysis. As a CS student, Aleksandar has very in-depth technical knowledge about computers, and he also likes to stay current with new technologies.