the only thing you need to worry about is if you use virtual machines - regardless the difference of these settings are negligible

 

are negligible but when u add 4 settings that lower your latency it makes you notice though ;D

 

bots everywhere

 

You can disable all of them. The only option from those menus that is useful to most end users is advanced error reporting. Without AER you can miss some warnings/errors that would otherwise show up in event logs. For example, I recent identified a PCI-E downstream switch port error that could have potentially lead to SSD corruption, which I was able to resolve with a small bump to chipset voltage, that would never have known about without AER.

IOMMU is required for x2APIC, which can mean lower overhead interrupts on some systems, even without virtualization, but IOMMU has some degree of overhead itself. Might be worth testing IOMMU enabled + x2APIC vs. IOMMU disabled and standard xAPIC...the difference will likely be extremely small in any case, however.

 

Might be worth testing IOMMU enabled + x2APIC vs. IOMMU disabled and standard xAPIC...the difference will likely be extremely small in any case, however.

I cannot boot into Windows with x2APIC and virtualization disabled (SVM Mode disabled and IOMMU enabled).

It seems like it should work but Windows stalls during boot, with the spinning circle forever. It boots fine with SVM enabled, but the system is slower.

 

VBS disabled, Secure boot enabled or disabled. It does not seem like this should be the case, but OS support for x2APIC is weird.

EDIT:
VBS was not really disabled. After finally disabling it I always stall during windows startup if I enable x2APIC because as part of actually disabling VBS (so it stays off with virtualization still enabled) I also disabled support for IOMMU.

I think it is a Windows 11 2H24 issue: IOMMU support is part of virtualization services. Disabling SVM Mode in BIOS also disables all virtualization features, so Windows stops supporting IOMMU either way.

View attachment 2717060
MSInfo:
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I have VBS and all of Microsoft's virtualization services disabled (I try to use as few first-party Microsoft anythings as possible). All of my systems let me swap between x2APIC and standard xAPIC, but there were some significant oddities with the firmware I'm using on my ASRock B650M-HDV + 9800X3D setup. Enabling IOMMU on this system destroys memory performance and makes USB shut down intermittently (maybe an issue with XHCI handoff). My other systems have almost no measurable differences between x2APIC and xAPIC.

So now i have only question about pcie ari, pcie ari enumeration and acs enable

ARI is mostly for sharing PCI-E devices with multiple virtual machines while ACS is a security thing to keep PCI-E devices from talking to eachother directly. Unless you're running a hypervisor, just leave them disabled.

i assume iommu is needed for x2apic?

Yes.

 

I have VBS and all of Microsoft's virtualization services disabled (I try to use as few first-party Microsoft anythings as possible). All of my systems let me swap between x2APIC and standard xAPIC, but there were some significant oddities with the firmware I'm using on my ASRock B650M-HDV + 9800X3D setup. Enabling IOMMU on this system destroys memory performance and makes USB shut down intermittently (maybe an issue with XHCI handoff). My other systems have almost no measurable differences between x2APIC and xAPIC.



ARI is mostly for sharing PCI-E devices with multiple virtual machines while ACS is a security thing to keep PCI-E devices from talking to eachother directly. Unless you're running a hypervisor, just leave them disabled.



Yes.

okay, i have last question. I have b450 aorus elite v2 and kingston a2000. They are saying that ten bit tag is for pcie 4.0 but when i enable pcie ten bit tag i see that everything runs smoother and apps are loading faster why?

 

is that 150 wattage not too high?

 

3600's just degrade because they feel like it

 

Im using audio interface (focusrite scarlett solo 3 gen) ,gpu gtx 1660 and kingston a2000 500gb if that matters.

Hi, check this https://www.kvraudio.com/forum/viewtopic.php?t=621326
BTW, make sure the motherboard BIOS is updated and there is a new chipset driver
version 7.06.02.123 from 2025-06-13.

https://www.amd.com/en/support/downloads/drivers.html/chipsets/am4/b550.html