Question A PCIe 3.0 graphics card, on a PCIe 2.0 board

[Zekiox]

Hello, I would like to know if a graphics card with PCIe 3.0, on my board with 2.0, my PCIe is very unfortunate:/ how much performance percentage would the graphics card be losing? I calculate about 10%

 

[Kaamos_Llama]

No need to calculate for your self

In this review, we are taking the fastest graphics card from NVIDIA, the GeForce RTX 2080 Ti Founders Edition, and test it across PCI-Express 3.0 x16 (the most common configuration for single-GPU builds), PCI-Express 3.0 x8 (bandwidth comparable to PCI-Express 2.0 x16), PCI-Express 3.0 x4 (comparable to PCI-Express 2.0 x8), and for purely academic reasons, PCI-Express 2.0 x4 (what would happen if you installed your card in the bottom-most slot of your motherboard). The table below gives you an idea of the theoretical maximum bandwidths of the common PCI-Express configurations:

NVIDIA GeForce RTX 2080 Ti PCI-Express Scaling

It takes a lot of bandwidth to support the fastest graphics card, especially one that can play anything at 4K 60 Hz, with an eye on 120 Hz. The GeForce RTX 2080 Ti could be the most bandwidth-heavy non-storage PCIe device ever built. PCI-Express gen 3.0 is facing its design limits.

www.techpowerup.com

So for the fastest PCI-E 3.0 GPU available, you would only lose 2% on average from using PCI-E 2.0, all other things being equal

HOWEVER !

Any motherboard without PCI express 3.0 is going to be from pre 2010. So depending on which GPU and CPU we are talking about, its very likely your CPU and RAM are going to hold you back far more than that.