Confusion about "Missing" PCIe Pins on LP RX 550

[XXX_BlueFire_XXX]

Hello All,

 

So been looking for an RX 550 graphics card from the second hand market for a project of mine. I came across a relatively cheap and obscure version of the card, which I believe to be the following: 6J78X Dell AMD Radeon RX550 4GB GDDR5, most likely pulled from some Optiplex. Most graphics cards containing the RX 550 GPU have a PCIe x16 pin configuration that I'm familiar with; however, this card seems to have a large portion of pins missing yet plugs into a PCIe x16 slot. It looks more suited for a PCIe x8 slot. I'm confused as to what this means for performance compared to others cards. Unfortunately, since no practical person would buy this thing outside of an Optiplex, there aren't any sort of benchmarks I can find to compare. I'm assuming it just means that bandwidth would be limited, though I wanted to ask the experts and possibly learn something along the way. I'll attach an image below showcasing what I mean.

 

Thanks all!

[Enderman]

Even an RTX3080 doesn't use full 16x bandwidth.

This card has such low performance that it is perfectly fine and not bottlenecked with 8x.

You could probably even run it at 4x without any performance decrease too.

[XXX_BlueFire_XXX]

@Enderman

Thanks for the info. I assume the extra pins weren't included simply because they weren't necessary.

[mariushm]

The GPU chip itself  only has 8 pci-e lanes, it could not use 16 pci-e lanes even if they were there.

 

Same story for RX 460 , 455,  RX560 and all the variants that use the previous "Baffin" series chip https://www.techpowerup.com/gpu-specs/amd-baffin.g796 ... the chip only has 8 pci-e lanes, because it's not powerful enough that you would actually benefit from 16 pci-e lanes.

 

Some video card models keep the pads and traces on the edge connector simply because they copy paste that edge connector layout from other card circuit board templates and don't bother to remove the extra pads,  or in rare cases the extra pads are used to transfer some heat from the video card into the slot and motherboard...

 

You could physically cut the edge connector to make the card fit into a pci-e x8 slot if you want to....