B550 or X570 mobo with PCIe 4 NVMe, Ryzen gen 4 & Radeon GPU ?

[MonsieurPropre]

Hi,

 

Despite being quite tech savvy regarding software (being a dev is helping in that regard), I'm kind of a newbie when it comes to PC hardware. I'm currently buying parts for my first build and there's still a question I couldn't answer yet: 

 

Considering I'll be using a PCIe 4 M.2 NVMe SSD (Aorus Gen4) along with a Ryzen 5 5600X and a RX 5700XT (also connected in PCIe 4), should I buy an X570 or a B550 mobo? My fear comes from some B550 spec sheets (thinking of the Gigabyte B550 Aorus Elite V2) saying that when you're using Ryzen Gen 4 (5xxx) CPU along with a Radeon PCIe 4 GPU, the PCIe 4 M.2 NVMe slot is limited to PCIe 3 speeds (which would be bad in my case, since I want to take full advantage of the PCIe 4 M.2 NVMe SSD I bought).

 

Is it true or just some marketing BS to make you buy a more expensive X570 board? If it's true, then is this limitation on all B550 models?

 

Thanks for you input and help on this! If you want to know the rest of my build's parts, feel free to ask, as I have already bought most of it.

[Electronics Wizardy]

B550 will work fine for your use. 

 

You can use a gen 4 m.2 and a gen 4 x16 gpu just fine on that board.

 

The gne 3 limit is for cpus without gen 4 support, basically apus

[bowrilla]

40 minutes ago, MonsieurPropre said:

Hi,

 

Despite being quite tech savvy regarding software (being a dev is helping in that regard), I'm kind of a newbie when it comes to PC hardware. I'm currently buying parts for my first build and there's still a question I couldn't answer yet: 

 

Considering I'll be using a PCIe 4 M.2 NVMe SSD (Aorus Gen4) along with a Ryzen 5 5600X and a RX 5700XT (also connected in PCIe 4), should I buy an X570 or a B550 mobo? My fear comes from some B550 spec sheets (thinking of the Gigabyte B550 Aorus Elite V2) saying that when you're using Ryzen Gen 4 (5xxx) CPU along with a Radeon PCIe 4 GPU, the PCIe 4 M.2 NVMe slot is limited to PCIe 3 speeds (which would be bad in my case, since I want to take full advantage of the PCIe 4 M.2 NVMe SSD I bought).

 

Is it true or just some marketing BS to make you buy a more expensive X570 board? If it's true, then is this limitation on all B550 models?

 

Thanks for you input and help on this! If you want to know the rest of my build's parts, feel free to ask, as I have already bought most of it.

The spec sheet doesn't actually even mention 4th gen Ryzen anywhere on the storage specs.

 

B550 is PCIe 3.0 internally, whereas X570 is PCIe 4.0. Both are connected with 4 lanes but the X570 one has (in theory) double the bandwith. The first M.2 slot is always connected directly to the CPU with 4x PCIe 4.0. Always. That's Zen architecture. 16x PCIe gen 4.0 from CPU to PCIe slot 1 (GPU), 4x PCIe gen 4.0 to M.2 and 4x PCIe 4.0 to chipset. This does not change whatever board you choose. The board manufacturer might fiddle around and give you more options (i.e. giving you a BIOS option to split up the 16x to PCIe slot 1 into 8x 4x 4x giving you 2 more PCIe 4.0 M.2 slots) but the basic config always works.

 

If you want (for whatever reason there may be, I can't come up with any) more than 1 PCIe 4.0 NVMe drive then xou need X570. Und you should definitely not plug in anything else into the ports that are connected through the chipset, because those will eat away from the only 4x PCIe 4.0 lanes from CPU to chipset.

 

I'd argue that a PCIe 4.0 NVMe is not noticeably faster in any real world scenario. You will pay quite a premium though.

 

Also bear in mind: X570 needs to be actively cooled and all X570 boards come with a chipset fan of usually dubious quality and in a very unusual size so you can't just simply switch it out. It can be an annoying source of high pitched nosie.

[freeagent]

I am pretty impressed with B550. I bought it to save a few bucks, but I guess I could have got a lower end X570 for the price. Whatever.. coming from an overclocked Z77 this thing is fast AF. It is very nice to use. I have had to clear the cmos quite a few times due to memory tuning.. so a button would have been handy dandy. 1.5 thumbs up from this guy.

[MonsieurPropre]

Thank you for all your answers, especially @bowrilla's which is very informative and detailed.

 

I'm going to go for a B550 then since it's much easier to get a good one with good VRM for less money.