Question If nowadays gpu and nvme directly talk to CPU then how come chipset doesn't support pcie 4?

[howdy.techy]

I am trying to learn about computer hardware, I learnt that modern cpu skips chipset and directly communicates to gpu and ssd. But then again there are few motherboard which supports ryzen 3rd gen cpus but do not have pcie 4. While this is not in the case of b550. So my question is if gpu and ssd directly communicates to cpu then why support for pcie 4 from chipset matters or how exactly stuff on motherboard works with each other?

I am certainly not obsessed with pcie 4, just want to understand basics of computer hardware so that I can be confident enough while building next system for myself and friends.

 

[Shektron]

I am trying to learn about computer hardware, I learnt that modern cpu skips chipset and directly communicates to gpu and ssd. But then again there are few motherboard which supports ryzen 3rd gen cpus but do not have pcie 4. While this is not in the case of b550. So my question is if gpu and ssd directly communicates to cpu then why support for pcie 4 from chipset matters or how exactly stuff on motherboard works with each other?

I am certainly not obsessed with pcie 4, just want to understand basics of computer hardware so that I can be confident enough while building next system for myself and friends.

I'm not an expert but from what I can tell, the difference is not just that the chipset is faster, but that the lanes themselves are different. While GPU and SSD communicate directly with the CPU, they still do so through the motherboard's PCI-e lanes. If the motherboard doesn't have PCI-e 4.0 lanes, they will not be able to communicate at those speeds. The motherboard not only needs to have a chipset that supports PCI-e 4.0, but the actual lanes inside the motherboard are also built according to the PCI-e 4 spec. Again I'm not an expert in this but this is from what I have understood in the past few years of following technology.

 

[howdy.techy]

I'm not an expert but from what I can tell, the difference is not just that the chipset is faster, but that the lanes themselves are different. While GPU and SSD communicate directly with the CPU, they still do so through the motherboard's PCI-e lanes. If the motherboard doesn't have PCI-e 4.0 lanes, they will not be able to communicate at those speeds. The motherboard not only needs to have a chipset that supports PCI-e 4.0, but the actual lanes inside the motherboard are also built according to the PCI-e 4 spec. Again I'm not an expert in this but this is from what I have understood in the past few years of following technology.

I appreciate you answer but confusion is still intact. How asus was able to support pcie 4 on b450 (TUF Gaming) just by an bios update if hardware was not according to pcie 4 specs?

 

[GarrettL]

It's PCIE 3.0 on B450 motherboards.

https://www.asus.com/us/Motherboards/TUF-B450-PLUS-GAMING/

 

[howdy.techy]

It's PCIE 3.0 on B450 motherboards.

https://www.asus.com/us/Motherboards/TUF-B450-PLUS-GAMING/

But nvme 4.0 can run at 5GB/s after bios update

View: https://youtu.be/vuJlmr0Mbz8


PCIE 3 x4 can only give 4GB/s

What's going on this case?

 

[GarrettL]

AMD removed this ability. Unless you can find someone who has that BIOS version saved.

Hard to sell new 4.0 hardware if this trick was left in the wild.

 

[howdy.techy]

AMD removed this ability. Unless you can find someone who has that BIOS version saved.

Hard to sell new 4.0 hardware if this trick was left in the wild.

I want to understand how it is possible of hardware doesn't support.