Dell has not eliminated the DPC latency issues that have been affecting the XPS 15 9570

[Redaktion]

Dell promised the earth, so it should come as no surprise that it has failed to meet expectations. The company had promised that it had fixed the latency issues that have been affecting the XPS 15 9570. Alas, it seems that the company still has some way to go before it eliminates these issues.

https://www.notebookcheck.net/Dell-has-not-eliminated-the-DPC-latency-issues-that-have-been-affecting-the-XPS-15-9570.420831.0.html

[splus]

DPC Latency Checker is not fully compatible with Windows 10 and might not show accurate latency. LatencyMon works OK with Windows 10.
So I just tried LatencyMon and you're right - I get up to 4000-5000ns latency with ACPI.sys when I press the brightness up or down keys.
That's huge and obviously something Dell needs to look at.

[bender007]

Hello. I have different experiences.
Also for your info, the high dpc latency is NOT on dell side, for the issue. Dell lowered it, yes...check on HP, Lenovo etc...exactly, it's laptop + win10 combination, although if you check older posts (2009) it did happen on win7. I've recently fired up win10 on macbook pro 2015, via bootcamp. Oh look...dpc above 1200..also please check with and without adapter - and kill the dell update etc.

[Nick Smith]

My experience with the lastest BIOS update is exactly what you have explained. It has improved but not been fix completely. Also yes I found the brightness button do trigger the glitches in my case.
Thanks for these updates I'm just hope that there is a resolution for this issue because it is a great laptop asides from DPC Latency and now it seems to drain battery faster in sleep mode.

[Daniel Kerr]

My system seems to be running ok.

I have both the xps 9560 and the xps 9570.

Also these are the docks I have are:

Razor core v1
Dell TB15
Dell TB16
Razor core x
Razor core x chroma

My xps 9560 works flawlessly with Dell TB16 and Razor core v1. Not tested with the other razer cores.

My xps 9570 if i come out of hibination and plug into a dell dock i get lag. I just unplug the dock wait for 2 beeps(2nd normally around 10 seconds) before reconnecting. After that it works flasslessy. No lag.

Razor core x chroma i bought a few days ago and seems ok after much messing around with drivers.  I had to force a few of them to use the non microsoft ones. I woke up, connected in the morning to my razer core then went to work and used my TB15 then came home and and connected back to the chroma. 1st time it has not caused a BSOD or lag. every time i connected it before rather the keyboard, mouse or network, screen was not working.

I installed the razer gpu switcher even though my system is dell.

very few times does a red spike appear. normally happens when installing programs.

Anyway hope the information helps. or if you need me to test any of the above combinations let mme know.

[mkdr]

DPC Latency Checker is not compatible with Windows 10, it shows bogus values, as stated on their website too:

Windows 8 Compatibility: The DPC latency utility runs on Windows 8 but does not show correct values. The output suggests that the Windows 8 kernel performs badly and introduces a constant latency of one millisecond, which is not the case in practice. DPCs in the Windows 8 kernel behave identical to Windows 7. The utility produces incorrect results because the implementation of kernel timers has changed in Windows 8, which causes a side effect with the measuring algorithm used by the utility. Thesycon is working on a new version of the DPC latency utility and will make it available on this site as soon as it is finished.

You have to use LatencyMon https://www.resplendence.com/latencymon

Bios 1.10.1 reduces the ACPI.sys latency by about 50%, to around 600ns, which is still bad, but better than anything before.

[blueyon]

Also this is a screenshot from my system while downloading 6 4gb movies, watching 1080p movie coding and graphic design apps running all at the same time. Everything is in the green.

I would post a screen shot but dont have enough posts.

[Daniel Kerr]

ok if i set the asix ax88179 speed & duplex in device manager to 10mbps everything works fine! mice, keyboard, screen LAN all working. I must have done it last night and forgotten about it.

if i put it to 1gpbs every time i restart something is not working. the dpc latency checker is all in green with 10mbps. problem is this is just to slow.
surely it should just be a matter of configuring the network card properly.

[Alex Alderson]

DPC Latency Checker is not compatible with Windows 10, it shows bogus values, as stated on their website too:

Windows 8 Compatibility: The DPC latency utility runs on Windows 8 but does not show correct values. The output suggests that the Windows 8 kernel performs badly and introduces a constant latency of one millisecond, which is not the case in practice. DPCs in the Windows 8 kernel behave identical to Windows 7. The utility produces incorrect results because the implementation of kernel timers has changed in Windows 8, which causes a side effect with the measuring algorithm used by the utility. Thesycon is working on a new version of the DPC latency utility and will make it available on this site as soon as it is finished.
...

Completely agree that Dell has improved things, but we are still getting the same spikes with LatencyMon. The article has been updated with LatencyMon results to reflect this.

[Daniel Kerr]

still having major issues. every time i restart something different is not working.

I ran Latency Monitor:

Your system appears to be having trouble handling real-time audio and other tasks. You are likely to experience buffer underruns appearing as drop outs, clicks or pops. One or more DPC routines that belong to a driver running in your system appear to be executing for too long. Also one or more ISR routines that belong to a driver running in your system appear to be executing for too long. One problem may be related to power management, disable CPU throttling settings in Control Panel and BIOS setup. Check for BIOS updates.
LatencyMon has been analyzing your system for  0:00:16  (h:mm:ss) on all processors.

[Daniel Kerr]

Just put the network speed to 10mbps again and everything is running fine.

If i change the network to 1gpbs again the network will disconnect every few seconds.

I can only conclude that the razer have put a cheap network and USB controller chipset.

[Daniel Kerr]

Just plugged in a USB network card and transfered a 4k film. seems a better. Need to see what happens.

[Daniel Kerr]

ok problem is back. I have now noticed the USB ports on the razer are only showing 3 in device manager. also it does not matter which razor core usb port i plug my mouse and keyboard into they will not be working when i restart. i have to uplug and plug into a different razor core usb port.

[Daniel Kerr]

Ok i went out and bought a Akitio node pro. Everything works. no lag, full speed network, plays games in 4k.

very disapointed in razer. big waste of money.

1 thing i did not try was using the hdmi port instead of DP. That might have reduced the bandwidth some what.

[Daniel Kerr]

I went for the pro version because it has 2 thunderbolt 3 ports. Just stick a USB hub in one and can have wired mouse and keyboard.