Does it matter which PCI slot I use for GPU?

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Trying to build a PC or just install a new GPU in your system? And after opening the case you found several PCI slots where the GPU can be connected. So, you are thinking which one should I use for this operation? And does it matter which PCI slot I use for GPU?

The answer to your question, in brief, is yes it does matter which slot you use for the GPU. Because not all slots on a motherboard are equal in their configurations. You should go with the first PCI slot for the GPU because it is the only true x16 PCI slot.

GPU is a very active component in the system. It processes and transmits more data than most other components. And a true x16 slot confirms the best possible route for this transmission. So, choosing the right slot matters. Let us explain it in detail for you.

Does it matter which PCI slot I use for GPU? – Detail Discussion

Does it matter which PCI slot I use for GPU?

You might at a first glance at all the slots think that it shouldn’t matter that much. But you are wrong to think so. It’s necessary to understand first what is going on with the slots on your motherboard. 

There are several types of slots that your motherboard comes with. There are x1 slots, x4 slots, x8 slots, and x16 slots on the board. And the number in the name of the slots indicates how many lanes they have. And the number of lanes determines the amount of bandwidth the slot can transmit.

As we have mentioned before, a GPU is a component that demands as much bandwidth as possible. This means depending on the slot the GPU is connected to; the performance of the GPU will vary. More lanes will ensure more data transmission at a better rate. And that’s why you need the x16 slot.

Which PCI slot should you use?

Which PCI slot should you use?

The short answer, as we have already mentioned, is the first PCI slot you find on your motherboard. Let us justify the answer by breaking it down to you.

The only true x16 slot

Which PCI slot should you use?

We know a graphics card or GPU should be connected to an x16 slot that has 16 lanes. But the problem is even if there are two or more x16 slots on your motherboard, only the first one has 16 lanes. The other ones might have 4 or 8 lanes. That’s why you need to choose the first x16 slot for the GPU.

Closest slot to the CPU

The GPU and the CPU have to work together to finish an operation on your computer. And for that, there has to be a lot of data transmission between these two components. So, the closest they are, the better the data transmission is. The latency will be the least in this case.

As the first x16 slot is the closest slot to the CPU. This is the best suitable slot for the GPU for it will ensure the best data transmission with the CPU.

Which slot is suitable for a low-level GPU? 

Which slot is suitable for a low-level GPU

This kind of GPU is made and used to support high-performance GPUs. They don’t require the bigger slots because they don’t produce that big amount of data. So, the transmission can be done through a slot with fewer lanes. And the best slot for a low-level GPU is the x1 slot.

The x1 slot has only one lane. And this is enough for the kind of data transmission that occurs from the low-level GPUs. The primary goal of these GPUs is to give additional display support. And this is not the most rigorous job a graphics card can do. 

You can plug in one of these low-level graphics cards to an x8 or x16 slot. But this will do no good to their performance. So, it is a waste. You should be reserving the bigger slots for the high-level GPUs. And the x1 slot is well enough for the low-level ones.

Can I put my GPU in the second slot x570?

Can I put my GPU in the second slot x570?

Yes, you can put your GPU in the second slot of an x570 motherboard. Of course, the best slot for the GPU is the first slot as we have discussed in great detail. But graphics cards can also work if connected to an x8 slot. Surely the data transmission will be a little worse but the job will be done.

From the user reviews of the AMD x570 motherboard, we have learned an interesting thing. After attaching the cooler, it is a bit tight for the GPU to be attached to the first PCI slot. And unfortunately, the x570 has only one x16 slot which is the first one on the motherboard. And the second one is an x8 slot.

But, the GPU will work just fine being connected to an x8 slot on the x570. The size of the x8 slot is perfect for hosting a high-performance GPU. Of course, the data transmission will be lesser than the x16. But this is a compromise you can make if needed and it won’t affect the GPU performance a great deal.

For better understanding, we attached a video below:


So, after reading the discussion above you shouldn’t get confused anymore about the PCI slots on your motherboard. “Does it matter which PCI slot I use for GPU?”, the question you had should not exist anymore. As you know the answer to it is an absolute yes. It does matter.

The reasons are simple enough to understand. And we have discussed them using the simplest terms. Not all PCI slots are made equal, nor do they have the same configuration. Depending on the type, the slot will have a different number of lanes in it. And we need the biggest number which is 16 for the GPU.

And only the first PCI slot is a true x16 slot with 16 lanes. So, this is the slot your GPU should go to. So do not use other slots unless you are compelled to do so. 

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Gary Scott

Hi There, I am Gary Scott, a Computer Engineer, and owner of this website. My friend and I created this website to share our knowledge, expertise, and experience with our fellow Computer community and pc enthusiast. I am a member of the Association for Computing Machinery (ACM) and the Institute of Electrical and Electronics Engineers (IEEE). I have been writing for Motherboard, CPU, GPU, RAM, Power Supply, Intel/AMD comparisons, CPU/GPU benchmarking, Gaming performance, Xbox, Play Station, and How to build your own PC. I will be regularly updating this website with new resources, If you have any questions or comments, please feel free to contact me.

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