Changing the USB polling rate

As standard, Windows will poll USB devices once every 1ms. However, this can cause the issue of laptops unable to enter the C3 processor power-saving state. By increasing the USB polling interval from 1ms to 5ms the processor can enter a C3 power-saving state during its inactivity.

There are also suggestions that decreasing the polling rate will also save energy generally. I’m not sure.

But, anyway, until I hear that all of this is some kind of urban myth, I’m willing to give it a try.

Here’s a couple of scripts (save them with .reg extensions and run them as required) that I rattled off to activate the “idle” (5ms) and also to return to “normal” (1ms)…

Activate Idle Polling Interval…

REGEDIT4 

[HKEY_LOCAL_MACHINESystemCurrentControlSetControlClass 
{36FC9E60-C465-11CF-8056-444553540000}000] 
"IdleEnable"=dword:00000001

Deactivate Idle Polling Interval…

REGEDIT4 

[HKEY_LOCAL_MACHINESystemCurrentControlSetControlClass 
{36FC9E60-C465-11CF-8056-444553540000}000]
"IdleEnable"=-

Or download them from here.