[SOLVED] Does it matter which PCIE slot I put my GPU in?

[barkersofgeraldine]

My GPU is currently in the second PCIE slot, and that's because the first one is not big enough for it

Ive had no problems with my GPU while its been there

I was just wondering if it makes a difference which slots I put devices in

 

[Endre]

My GPU is currently in the second PCIE slot, and that's because the first one is not big enough for it

Ive had no problems with my GPU while its been there

I was just wondering if it makes a difference which slots I put devices in

You should use the PCIe x16 @ x16, which usually is the top slot on the motherboard.

 

[lvt]

If it works it doesn't matter.

 

[syfari]

You're going to want to use the PCIe x16 slot, this is usually the top one; but it should be labeled in your motherboard manual. The other slots will work but you might see a decrease in performance depending on the GPU model.

 

[Schlachtwolf]

Just how do you mean not big enough? Cooler clearance? What GPU are you installing?

If it is a real high end card a single digit % reduction in fps is to be expected between the top x16 lane slot and the second x8 lane slot. On a midrange GPU, say an RTX 2070, there will be in prctical terms not much loss if any.

 

[Endre]

If it works it doesn't matter.

Well, actually it does matter.
You can insert the GPU in a PCIe x16 @ x8, or even more dramatic scenario: PCIe x16 @ x4!
It will work, but at a lower speed.

PCIe x16 @ x16 is the optimal slot.

 

[datoneboiwithanari]

If it works it doesn't matter.

still probably throwing away bandwidth

 

[Schlachtwolf]

A midrange GPU/CPU config does not even saturate the full x8 bandwith running games. So no issue throwing away bandwith you 'aint using anyway. On real highend platforms lokje a 6800xt, RTY 3080 and up, running hardcore rendering software and workloads then yes you need all the bandwith you can get. I think barkersofgeraldin has 2 options. Be happy with a working GPU in the second slot, taking a very minor performace hit or invest in a new cooler that allows the use of the top slot (which I presume is the clearance issue he has).

 

[InvalidError]

A midrange GPU/CPU config does not even saturate the full x8 bandwith running games.

Say that again with a 4GB RX5500. It performs as much as 70% faster on 4.0x8 vs 3.0x8. That thing could have really used a full x16 interface. The GPU situation being what it is, 4GB GPUs are going to be the best that cost-sensitive people will be able to afford for a while as far as the new-ish stuff is concerned.

 

[Wolfshadw]

How about we table such discussions until the OP returns with more details.

Wolfshadw
Moderator

 

[hotaru.hino]

As far as performance on PCIe bandwidth is concerned: https://www.techpowerup.com/review/nvidia-geforce-rtx-3080-pci-express-scaling/27.html

Considering the RTX 3080 on average doesn't see a <15% performance drop until you get to PCIe 1.x x8, I would argue it largely doesn't matter.

Exceptions like the RX 5500 XT are due to certain conditions that can be easily worked around.

 

[InvalidError]

Exceptions like the RX 5500 XT are due to certain conditions that can be easily worked around.

It will get worse as lower-end GPUs get faster and games continue using more VRAM.

 

[hotaru.hino]

It will get worse as lower-end GPUs get faster and games continue using more VRAM.

And hopefully we'll see a progression of how much VRAM these lower end cards get. But as it stands, the RX 5500 XT is still an exception.

 

[InvalidError]

And hopefully we'll see a progression of how much VRAM these lower end cards get.

Have you looked at GPU prices recently? There is a $300 street price difference between the 4GB and 8GB RX5500. Having less VRAM than the DAG size is the only thing keeping modern lower-end GPU prices remotely sane. Until the mining situation is resolved, 4GB is the most VRAM a budget GPU can have.