M17x and DPC Latency

Hi guys,
I would like to know why the M17x has DPC latency :
Look mine under Win7:


NDJason2009 under WinVista:



ex2j under win7 :



I'm almost sure all the M17x have this problem and I would like to know how to fix it...

Youc an download this software here :

http://www.thesycon.de/deu/latency_check.shtml

 

Honestly I have never heard of DCP before or that tool. What is the point of it?

 

Goddamn that's high. How many background processes do you have running?

 

This has been a reoccurring issue with many laptops. There is a very long thread here which may be of interest to some... A big factor has been the wifi card. Some people have reported that switching off the unused band coverage has helped... IMO there really is no simple fix.

Another thread on this can be found here.

 

All my applications were closed.

I have try to disable all the device in the device manager (one by one) and there's no change.. :/

 

Yes I didnt know of this until I started reading here.

I downloaded and mine appears like this one here...
I have BT and wifi off.. I will have to tweak things and see what is causing this.. I should format, and just install basic drivers and go from there... No alienware software ect... maybe even before antivirus ... Just to see when it appears..

 

I did this but doesn't work. the problem appear the first time windows is start.

 

Hrm.. to bad this program wont tell you exactly what is causing the spikes.. lol

Its like, something is not right but you figure it out.. ahaha

 

does this even matter....? is it something to even be worried about?

 

cracking sound in movies and musics...

 

Do you ever hear your audio drop out for a second or crackle? It's noticeable to me if I'm just trying to listen to music. It sometimes won't happen and sometimes it happens very often. This latency is what is causing that. It may not be a serious problem, but it's enough to be annoying. I wouldn't want to do something like DJ with the laptop if the audio drops out or crackles randomly.

 

ok, now why couldn't someone just say THAT in the OP haha

Haven't had my system long enough to notice any of this yet....

 

I hate it when on vent.. does it all the time... very annoying.

 

I have sent a PM to Alienware-james and Alienware-Armando for this problem maybe they'll answer.

 

I have tried everything to get this too stop. I have to use my old Sony laptop for all my guitar stuff now. Oh well it's a good gaming laptop but sucks for anything audio related.

 

Curious to know if everyone experiencing the spikes. They wouldn't happen to be quad machines would they? Just thinking out loud.

 

My bet is speedstep, anyone tried disabling it?.

Try using it from ac and removing the battery too.

 

hrm.. I will try that..

for the heck of it, I ran this program on my desk top and all bars were green.. no spikes.. lol..

I am definitely interested in isolating what is causing this on the notebook..

 

Is there a way to disable it? I haven't found out how if there is and would very much like to know!!

 

That's something you normally disable in the bios. I don't remember it being a bios option for the M17x. You can also look to see if there is an option for C1E but I believe not all procs have C1E support.

 

I've watched countless HD movies on my M17X since I've had it and even though the DPC latency test shows I have spike up to 8000u, I've never heard anything off during the movies. I've never heard a cracking sound or anything like that. I think this test is useless...

 

It's better for people who actually record audio.

 

well recording != playback........people are acting like this is the largest failure ever......so the notebook works fine but doesn't record well?

How is that a shock....the microphones aren't what I would call studio quality anyway

 

I don't record audio, but the latency IS a big deal to me. I hear audio breaks and stuttering all the time, and it only happens when the latency shoots up. Its really bad, and takes away from games and even just simple music playback.

 

Sounds like you have it worse than others. Have you tried contacting Dell on this one?

 

I see, well I will just go on hoping it doesn't affect me...hasn't yet but I have not done much audio stuff with the notebook yet

 

My speakers are usb and when I had them plugged in through the hub on my cryo I heard it. I have not heard the pops since I plugged them directly into the M17x.

 

interesting. it does make sense that a hub would add latency, any known issues when using the 3.5mm jacks? This is how I would be connecting my Z-5500s to my M17x

 

Maybe it's the time to Alienware to make a bios to fix that, this'll more simple for everyone, i have sent a PM to Alienware-Armando and alienware-james but i don't think they are interested with this problem......

 

If it's a real concern then yes AW should hear you out. Were you able to isolate the application and/or driver that is causing the latency?

 

I just downloaded that latency checker..the bars never jumped over 2000 in stealth mode, in high power mode I got spikes at regular intervals though but between the spikes it stays under 2k.

 

If the DPC latency is too high this can affect playback too.

And it isn't just about recording... Any music production IMPOSSIBLE with that latency, Depending in what you do this can be the largest failure ever (TBH i would be impressed if that much spikes isn't affecting playback).

PS: Who the hell gonna use the onboard mic to record? lol.

@airplane

> 200 spike = pop in any music production software... Imagine 2k

 

I see, new to this DPC stuff....just watched an hour and a half of movie though with no audio anomalies of any sort. Haven't run that program to check my latency though - I may be ok.

 

Yeah, imagine 32000 spikes... awful. Absolutely awful. I'm almost positive some power management stuff is causing the bad latency on these machines. Interestingly enough, it spikes far less using integrated graphics, but still spikes. The only time it doesn't spike above 2000 is when the graphics drivers are uninstalled.

The problem with calling Dell or Alienware is that its not something that can be easily troubleshooted over the phone. And looking at the charts of others, I see its standard for these machines. I'd LOVE to have a direct conversation with the brilliant minds that developed this BIOS though. At least an option to disable all the power/thermal management and run all out full throttle all the time.

 

I get really high spikes, windows 7 has a built in DPC checker, I have it real bad on my machine. but i think i need to reinstall windows. and Win 7 RC may need some tweaking. ill try vista 64 after i get my SSD and my 4gb ram and see what i get. What video drivers is everyone running?

 

Want to find out what is causing the spikes? Bing:
xperf dpc

First hit is good:
Measuring DPC time
http://blogs.msdn.com/peterwie/archive/2008/10/06/measuring-dpc-time.aspx

 

Interesting, I read on another forum that other people think the nVidia drivers are causing the latency.

 

Can you take a screen with and without stealhmode please.

 

My DPC Latency under Vista64:



According to Xperf:

• The 2000-4000ish spikes every ~2 seconds are related to acpi.sys (probably the system checking battery status/fans and can be fixed by a BIOS update).

• The 60000ish spikes - which will cause audio crackling/stutter - are done by dxgkrnl.sys and most likely coming from the Nvidia drivers.

 

Yeah sure, I have to go to work now but I will do it when I get back.

 

I was doing some searching as well and some people seem to have this latency problem more with windows RC1, which i am using, and Nvidia products. Maybe a good bios update would be the Fix, or better drivers for the chipset, but who knows.

 

I can agree that this definitely causes problems even during normal use, like gaming or listening to music. It doesn't seem to be as frequent now as when I first got the laptop, but it's definitely still there.

Glad to see people know what the issue is, hopefully there's something that can be done.

 

Left is full power mode with graphics on high performance, right is stealth mode.

 

The sad is that i don't see dell fixing it... Every dell notebook out there have DPC latency problems and i never saw dell doing anything to help

 

I got my friend to run this program on his HP laptop and it averages ~230, and spikes to around 1000 every now and then so it is much better. Leads me to believe it is an Alienware program causing this.

 

I am sorry if this was covered, but what would an ideal and/or generally good reading from this program look like?

I ran this on my laptop and got a result just like NDJason2009 in the OP

For what it is worth

 

Good would probably be >100, OK would be >2-300 I imagine. My desktop never goes over 50, to give you a frame of reverence..

 

Any green latency without spikes is good

 

my desktop barely shows green. I wish my laptop was the same or even close.

 

Hmmm just tried this on my M17, and apart from one or two spikes over a couple of minutes to less than 1000, probably when I was doing something, I was consistantly under 100, that said Im not using any AW software.