I'm on Windows 7. I just ran a Power Efficiency Diagnostics Report through powercfg -energy and I got this error:
Platform Power Management Capabilities:PCI Express Active-State Power Management (ASPM) Disabled
PCI Express Active-State Power Management (ASPM) has been disabled due to a known incompatibility with the hardware in this computer.
I did some research in the Microsoft forums and it seems like a lot of people have this issue, but MS hasn't given anyone any satisfactory answers:
If there's anyone at Microsoft who actually knows what the "known incompatibility" is, they aren't saying. After searching Microsoft's website and the web for an answer and finding none, I've come to the conclusion that this is another one of those incomprehensible Windows messages that Microsoft tries to ignore ("...consult your original equipment manufacturer for assistance...") and nobody else can figure out.
from: http://answers.microsoft.com/en-us/windows/forum/windows_7-hardware/pcie-aspm-is-disabled-due-to-a-known/6ca12628-42ca-4804-af75-948199a7538a
more: http://answers.microsoft.com/en-us/windows/forum/windows_7-performance/platform-power-management-capabilitiespci-express/8611ba23-8091-46ac-b1f3-97cba5b43455
Have any SuperUsers encountered this "hardware incompatibility" and figured out a way around it?