I have a Dell XP 9570 i9 (HD) which I've only had for a couple of weeks. Apart from not waking from sleep which I've managed to cure I have terrible lag with my external USB keyboard and mouse. Initially I thought it might be the StarTech dock I was using but some testing has led me to believe it is a hardware/software issue with the Laptop.
The symptom is that as I type for a few seconds it will be fine and then it starts to lag and then it repeats keys. Eventually it settles down and then the issue starts again.
I have tried:
I'm not sure where else to go with this, but given that I know my docks work with other Laptops/PCs with the same keyboard(s) it MUST be related to the laptop software orhardware.
When you have access to important data a repeating delete key can be disasterous.
Solved! Go to Solution.
Just as a final test I tried turning c-state control back on in the bios and the issue returned immediately. So either c-state control is directly causing the issue or something else is causing c-state control to hiccup - maybe something is slowing the core state change so much it becomes noticeable.
Anyway hope it helps someone!
I can confirm that the mouse/keyboard lag and repeating keys appears to have gone away with my home peripheral set-up even with the wired mouse/keyboard plugged into a startech dock. I had the issue both at home and at work and whether the dock was involved or not, but it was far worse with my home wired keyboard.
I've no idea why changing c-state control would fix my issue but I mention it in case it helps someone.
Big thanks @pherrman, it was driving me insane. I've found just disabling c-state control appears to have done the trick for me, although I haven't tested it on my mechanical keyboard yet which was the worst. I'm on the 1.7 bios. I think the fans are running a little more but barely.
Not being able to use the keyboard and mouse was frustrating and potentially disastrous if the delete key stutters!
You've saved my bacon! 😁
It runs at full speed, no problem. Also the fans are fine as well. They don't spin up. Im not sure exactly what is happening but it may help alittle. Also I have noticed that bios 1.5.0 is the most stable. So I recommend that everyone update to bios 1.7.0 and see if the problem is fixed, if not then downgrade to 1.5.0
OK, so I disabled C-STATE CONTROL only in the BIOS and so far my keyboard lag and mouse stutter seem to have dissapeared. I'm not entirely happy with this as a resolution but it will do for now!
Anyone from Dell interested in this, there's clearly some issue with the CPU management!? Just for the record I have the i9 just in case it's CPU specific!
As far as I can tell C-STATE just controls the CPU when it's idle - it reduces the power consumption when there's no load on a core. Speed step on the other hand alters the speed of the processor when it is active. I've left speed step on. Disabling C-STATE appears to be reasonably safe but will increase the power used (i.e. will increase battery drain) and I guess may cause some small increase in temperature.
Thanks @pherrman - if you disable that what speed does the CPU run at? Is it likely to run slow or run at full speed, and if the latter is there likely to be overheating issues?
It's interesting you say that as I'm getting DPTF error messages in the Event viewer like this:
ESIF(8.4.10501.6067) TYPE: ERROR MODULE: DPTF TIME 30916005 ms
DPTF Build Version: 8.4.10501.6067
DPTF Build Date: Feb 16 2018 13:31:38
Source File: ..\..\..\..\Sources\Policies\ConfigTdpPolicy\ConfigTdpPolicy.cpp @ line 167
Executing Function: ConfigTdpPolicy::onBindDomain
Message: ConfigTdp not supported.
Participant: TCPU 
Domain: PKG 
Policy: ConfigTDP Policy