Graphics Cards

[sanjdagr8]

So, My RTX 2060 recently stopped working and I am looking to upgrade my GPU and have decided on RX6750XT. I have a MSI B450M motherboard (https://www.msi.com/Motherboard/B450M-PRO-VDH/Specification). My CPU is Ryzen 5 2600 and PSU is Coolermaster 650W Bronze. I know that I might face a CPU bottleneck but I am going to get a powerful GPU now and upgrade on the CPU later. Now for the question in the title, The motherboard's website says it has 1 PCie 3.0 x16 slot. The GPU is a PCie 4 graphics card but I read on various forums that PCie 3 works just fine and it just requires a x16 slot. So technically I can install this GPU on my rig, However the tech guy I gave my PC to fix it says that this powerful GPU is not compatible with my old motherboard. 

Can I install a RX6750XT on my current CPU, motherboard combination?

[Stigmakso]

Yes you can, without a doubt.
A 6750XT is not able to saturate the bandwidth of a gen 3.0 x16 slot.
It's only been seen with a 4090 on a gen 3 and you only loose 2/3% performance but it's still compatible.
Your tech guy is out of the loop (or lying to you).

[jerto]

^ this, idk what the tech guy is on about

[Mooddie]

correct

[elstaci]

Generally PCIe is downwards compatible.

A PCIe x 16 x 16 3.0 would be the same as a PCIe x 16 x 8 4.0 slot.

Just means that the PCIe 3.0 slot would have half the bandwidth speed of a PCIe 4.0 slot.

PCIe x 16 3.0 has a maximum per lane transfer rate of 8GB per second while the PCIe x 16 4.0 has a maximum per lane transfer rate of 16GB as per this tech article: https://computertechnicians.com.au/pcie-4-0-vs-pcie-3-0-whats-the-difference/

What Is The Maximum Bandwidth Of PCIe Gen 3?

The maximum bandwidth of this standard: is 8 Gigatransfers per second (GT/s). This means that 16GB of data can be transferred in less than two seconds

What Is The Maximum Bandwidth Of PCIe Gen 4?

The first thing to note about PCIe 4.0 is that its maximum data rate has been doubled compared to PCIe 3.0 – from 8 GT/s to 16 GT/s. This means that each lane can transmit up to 16 Giga transfers per second in both directions simultaneously.

Now the issue I might see is if your GPU card can operate in a PCIe x 16  3.0 slot or it is engineered to work only on a PCIe 4.0 slot. 

I have read that some Users, here at AMD Forums,  needed to set in BIOS the GPU Slot from 3.0 to 4.0 for the latest AMD GPU cards to work correctly or even work.

My Personal opinion would be the card should work in a PCIe 3.0 x 16 slot without issue just possibly in certain circumstance not as fast and certain GPU features may not work or work as well.

Either way I would open a AMD SUPPORT Ticket - https://www.amd.com/en/forms/contact-us/support.html  and ask them directly if that GPU card is compatible to work in a PCIe 3.0 slot or not.