Hi need some support on PCIe 4.0 I'm planning on building a gaming/editing PC and looking at the ASUS TUF Gaming B550-PLUS. My understanding is that the B550 chipset doesn't support PCIe 4 yet the specs onsite the ASUS say that it does support it so I'm confused. My Question: Can someone help clarify if it this MOBO does have PCIe 4.0, or am I missing something? My planned PC Spec: ASUS TUF Gaming B550-Plus Samsung Evo 970 plus (I know this is PCIe 3, but seems plenty quick enough compared to current NVME PCIE4 SSDs) 3070 Ryzen 5 5600x 2x16 GB 3600 RAM FYI, planning on PCIe 4 for future proofing purposes- I tend to keep my PC for many years before replacing the mobo, but have changed the primary SSD a few times so it seems likely a PCIe 4.0 will be needed at some point. It's the video editing part where I'm most concerned about, hence hard drive speeds matter. Any further build advice would be appreciated! Links: https://www.asus.com/.../All-series/TUF-GAMING-B550-PLUS/ Thank you!
TBH PCIe 4.0 is a bit of a gimmick, its likely nothing you will do on it will even use let alone you'll be able to tell the difference betweek 3 and 4. LTT did a blind taste test of various SSD's and SATA to PCIe 3 could barly be noticed and 3 to 4 was impossible to tell the diffrerence. Which makes sense as SATA to PCIe 3 is something like 3-5 times faster, and massively improved latency, while 3 to 4 is only twice as fast at a push (most mid to low teir ones will be almost the same as a high end 3) and the latencies while faster are much more similar. There just isn't a massive speed boost to be had. Now will games use PCIe 4 for loading? Possibly, but I'm willing to bet 3 will be fast enough for most. Going back to your question though, I think AMD doesn't ceritfy B550 for PCIe 4 but Asus has the electronics in place for it to operate, and 3xxx CPU's doing have 4 and can use that platform, so those two things are where the confusion comes from. I think PCIe 4 works on that board with that CPU.
All B550 boards support 20 PCIE4 lanes to the CPU, generally split between the pcie x16 slot and one of the M2 slots but options and splits vary by board. The additional lanes provided by the chipset itself are all PCIe 3.0. X570 on the other hand has the same number of lanes from the CPU, plus all the additional lanes provided by the chipset are PCIe 4.0 as well.
B550 doesn't support PCIe 4.0. But the CPU will do, so as said, the 20 PCIe 4 lanes are split 16x on the primary PCIe slot and 4x on the M.2 NVMe drive slot next to the processor. Yes, this motherboard does have PCIe 4.0. But only on the primary PCIe slot and the M.2 NVMe slot next to the CPU. I have the mATX Wifi variant of this Asus TUF B550 motherboard.
Chipset picture would have probably helped The pcie3x4 link from CPU to Chipset in the middle could be considered the PCi express divider Stuff from the left comes from CPU and is gen4, so that would be your first couple of PCIe slots and M2 depending on how board is configured Stuff on the right is from chip set is Gen 3 and again how these are used will be board dependent.
