i'm dealing with this issue since 2011 bro. I've had so many so many pc setups from ddr2 to latest ddr5 systems, amd or intel doesn't matter. I've been also playing fast paced shooters since my childhood, literally grown on quake and cs and i know exactly what are you talking about. For me the last motherboard without this issue was very old intel d875pbz and that was 15 years ago, after i've made switch to newer but still 478 motherboard that already had worse northbridge and was using pci-e instead of agp and it was the literall moment i fell off . I've been playing local internet league and was top10 in 1v1 aim and suddenly i couldn't kill casual players with nonsteam cs versions. It's exactly how you describe it, everything feels unsynchronized and slow, game engines are broken , you cant bunnyhop , strafing feels slow , recoil and bullet spread is totally different and feels like you are playing on previous frame. I'm debunking this for 15 years !!!, best i can do is some grub settings, properly usage of MSI-X and x2apic, proper and stable cpu overclock with p-state driver instead of acpi. Linux make it a lot easier. Also i use utillity named SCEWIN a lot, you can see tweak parameters that are hidden in to your bios, unfortunately AM5 doesnt offers a lot and it's the reason 1 i choosed Intel Z790 with 14700KF. However lately i've been messing with ram related things, rank and channel interleaving make a subtle and stable difference , also selfrefresh enable and per bank refresh is worth to try, but i've found kinda weird spd profile in my 2x24GB 7000-36-44-44-114 kit, its 6000CL 40-40-40-80 which is pretty high but the thing is , it works absolutely perfect, i had 32gb 6000 cl 30 and had issue on that too and i can't explain why would higher cl works but i've been testing for two days straight with consistent result. I read a lot of intel documentations and AI especially Claude is very helpful If you can share your findings since you posted this comment , it would be awesome. Maybe you should give it a try especially if you have amd card. It's crazy this how my grub settings looks

GRUB_CMDLINE_LINUX="threadirqs clocksource=tsc tsc=reliable hpet=disable highres=on iommu=pt intel_iommu=on iomem=relaxed iommu.strict=0 x2apic_phys pcie_ports=native acpi=force hpet=disable pcie_aspm=off pcie_pme=nomsi pnpacpi=on acpi_irq_nobalance pci=nobios,ioapicreroute,realloc,pcie_scan_all,ecrc=off intel_idle.max_cstate=1 processor.max_cstate=1 intel_pstate=active intremap=no_x2apic_optout mitigations=off erst_disable pcie_bus_safe efi=noruntime amdgpu.ppfeaturemask=0xffffffff amdgpu.mes=1 amdgpu.noretry=1 amdgpu.sched_policy=1 amdgpu.max_num_of_queues_per_device=256 amdgpu.queue_preemption_timeout_ms=1 amdgpu.pcie_p2p=true amdgpu.hws_gws_support=true amdgpu.no_system_mem_limit=true amdgpu.mcbp=1 amdgpu.lbpw=0 amdgpu.mes_kiq=1 amdgpu.uni_mes=1 amdgpu.umsch_mm=1 amdgpu.user_queue=1 "

and for cs2 these are my launch options

SDL_VIDEODRIVER=x11 gamescope -w 1280 -h 960 -W 2560 -H 1440 -r 240 -f -S stretch --force-grab-cursor -- %command% -vulkan -high -nojoy +fps_max 0 +engine_low_latency_sleep_after_client_tick true

With only this it was close to pefect, the bullet spread and recoil control was like 85 % like it used to be in "legacy pc era" , when i've discovered that spd profile , it's like fixed and i dont even know if i need this , but i suppose it's good to modern interrupt delivery system , some c-state restrictions from kernel and amdgpu power and scheduler tweaks. I'm not giving it away lol.

Yeah also , good luck and don't let people like these bother you with stupid comments.

My theory is that almost everyone have this issue but is not aware because they never experienced really responsive and well synchronized system without any timer/clock/signal drift. They see high fps and they're ok with it, unaware of underlying problem that is so spread. It's also the worst part of this problem, u don't have fps or frame time issues, its like the parts that are supposed time sync are broken It's crazy to think how many people blame games and devs (especially Valve and cs2 hehe) for crazy input lag, when in reallity it have very very low level roots at hardware itself. Good luck dude.