I see a lot of reports from RTX 4000 and 5000 card owners with B550 issues such as very slow systems or crashing.
I have upgraded from an AMD 6800XT , which was running ok, to a 5070Ti which was crashing whenever I did anything much randomly...
It could run benchmarks, but even while idling it would just crash for no reason with a black scree, and a couple of minutes later system reboot.
Digging in event viewer I found and disabled Oculus services (VR) and that seemed to stabilise things a while, but after thinking I'd solved it with 5 hours working fine, crashes happened again.
I found and removed ALL startup software , especially ASUS Armoury crate and lighting, and tirned this off in the BIOS. Nope.. still happening.
Then I noticed PCIE 4x16 was running at full x16, where my last 6800XT had inexplicably been running at pcie4.0x8 only (made no difference to benchmarks). This was with BIOS hard set to use PCIE4, and with PCIE settings on AUTO . So I tried changing PCIE to 8x8 - this has capped the 5070Ti to Pcie4.0 x8, and everything has been running well (touch wood) for ~5 hours . I was unable to make it crash even by doing a large fast file copy to an external SSD while playing spotify, watching a yotube video and having a game of minecraft (bluetooth keyboard and mouse, and lots of network traffic to local server).
So long story short I think the lack of PCIe lanes on B550 is the issue, and hitting up against high bandwith use of the PCIE 4.0x16 seems to be causing the crashes... Maybe this isn't such an issue for X570 users with more lanes, or PCIE 5.0 boards but for now PCIE 4.0 x8 seems to be required to get stability
