Since I first blogged about DPC Latency and the Alienware M17x, we’ve been working toward a solution. Since then, some of you may have read Engadget’s update post on the topic last week. Thanks to everyone who responded and sent me their service tag. It helped us understand exactly what everyone had done to try to resolve their difficulties, and confirmed a lot of what we already knew.
I’m very happy to share that engineering has discovered a solution for the DPC latency issues on the M17x. This process will resolve the DPC latency problem on all machines with a Dell factory image. Dell can’t guarantee that this solution will resolve issues on machines that have been modified by their owners.
Update 2/23: As readers of NBR and Engadget may already know (see Update 2 in Tim's post), we've sent some Aliens out to claxdog's house to check on the behaviors some people are seeing in the field. They were able to compile some data that should help them get to the bottom of what else is causing this. When I have more details to share, I will.
Without further ado…
If you’re one of those who suffer from DPC latency issues, a quick run of DPC latency checker will likely yield you results similar to this:
If this is you, and you need the issue resolved immediately, follow this three step process:
Following this process has consistently yielded the following results using DPC Latency Checker in the lab:
As you can see, all red is gone.
If you’ve followed the above steps exactly, whatever issue you’re experiencing isn’t likely to be caused by any DPC latency resulting from the factory configuration, or DPC latency at all in many cases. As I said before, Dell can’t guarantee that third party software will behave itself after you install it.
Either way, if you’ve confirmed you still have a problem after following the above steps, run the DPC Latency Checker. If you’re still getting DPC latency spikes for some weird reason, and I seriously doubt you will be, let me know here in the comments or send me a private message with your service tag number.
Update 3/19 - A few days ago we made a beta driver from nVidia available to folks on notebookreview.com, and so far, the results have been pretty positive. If you're a customer who's seeing DPC latency problems and have the nVidia graphics cards on your m17x, you may want to give this a shot.
M17x nVidia Beta Driver
Bear in mind this is a beta, and as such it is still a work in progress. If you opt to try it, please remember the following:
I'll post back here when there are any changes, or when a finalized version of the driver is released.
Update 3/22: For those of you who haven't already heard, an updated driver release for this specific issue has been posted on support.dell.com. Reports are that it's working well, with the only DPC latency spikes when a CD/DVD is ejected remaining. This specific behavior is still being investigated, but will be resolved in the future, and is fairly minor and easily avoidable.
For those of you who have swapped to ATI cards for this issue, our friends at NotebookReview have started a thread about specific issues you may encounter.
Thank you everyone once again for all of your patience regarding this issue.
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unfortunately this has not solved the nvidia gpu's upclocking /Downclocking i still have the same issues that i have previously mentioned to you.
I just ran the script. DPC Latency has actually worsened for me since doing this. Personally at this point I'm a bit confused how the in house engineers can get such good results while the rest of us can't. I still trust you guys to figure something out, but this fix seems to do little more than what many of us have already done manually, without positive results.
Start some music, and launch a game. That's all it takes to see the problem. The mystery is how the computer was ever released in a state like this.
Oh dear another "fix" that doesnt work. Cant wait for another one.
If the fix doesn't work for you, first please verify that you've tried the following steps, in order:
1. Verify you have BIOS A03 installed.2. Run the script.3. Uninstall and re-install the latest Dell posted WLAN driver.After you've done all that, contact me with that information, and send me your service tag. I'll be compiling that because I know my engineering friends are going to want all that information.
Same boat here a03 bios ran script uninstalled and reinstalled wlan driver worse than before.
1. Yes, definitely running A032. Done3. Ok, already had the driver but reinstalled anywaysI still have problemsI can not believe what is happening
Even the Bios A03 did not work I still get red spikes. When are Dell realising that it will have to replace this system with a new one or gives us a refound? We do not wish to wait for any more so called solutions. We just want what we paid for. We need to be able to use our laptops now and not six months later. How many times do we have to reinstall these drivers? Read the comments here.
All you have to do to get those massive spikes is one of the following
1- Run a video or audio file.
2- play a game
3- run a video on youtube.....
Do any of the following and post the latency checking readings, i bet you a $100 we will see at least 2 red bars every minute. Of course you will not see any red spikes with the laptop setting idle doing nothing........ it doesn't take an engineer to figure this out...
Are you kidding me!?!?
Is this the log awaited "fix" that we have been told about?
Not fixed. I think you folks are grasping at straws.
Also, what OS did you test this on?
Hi. I am going through these steps and have run into a snag. Let me know what I should do next.
I had not made any changes to my system except to turn off SLI which seemed to help. Mostly I was waiting for an official fix. Now that this seems to be it I'm trying.
I installed A03. It seemed to go fine. It rebooted but when Windows started back up it ended up with a blank screen - just a mouse symbol. After trying a few times I thought maybe something was going on with the graphics cards (I have dual Nvidia 280s). I went to the Bios menu and disabled hybrid graphics. Sure enough it started up fine. I went through the remaining two steps. Installed the mass storage controller and WLAN updates fine.
So the computer is working, but my graphics cards are not on. When I try enabling hybrid graphics I always get the same blank screen with just a mouse symbol.
Could use some help. Thanks.
John, I don't want to get upset about this, particularly because you are only the front person and not the engineers responsible for diagnosing this issue. Why the hell are they continuing to ignore the evidence provided by the community. Most of us from notebookreview.com have already been on the Windows storage drivers for ages.
We have continued to post evidence of the GPU down-clocking issue (i.e. side-by-side DPC Latency + GPU-Z clocks) show the large spikes hitting when the cards change clock speeds. This happens allot, even when browsing the web or viewing on-line movies.
Here's my evidence for you. Notice the GPU clock changes...
i get the feeling you guys are STILL TESTING THE ISSUE ON VISTA.
and that screen shot was probably taken while idle.
please get win 7 and try it out, the issue is much more obvious in windows 7
i have a fresh windows 7 home premium 64 install, a03 bios, all dell drivers and nothing else installed except games which i use to test. oh and NO storage drivers installed.
and guess what?
this is an ss on idle
<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/sRQT0sTumhs&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/sRQT0sTumhs&hl=en_US&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>
if you say that dell cant guarantee 3rd party apps will not cause the dpc then what is this laptop for if dell cannot guarantee it can run ANY GAME without stuttering due to dpc latency?
$7000 paperweight anyone?
There is NO REASON for us to keep waiting. its been over 6 months since you guys have discovered the problem and since you cant fix it, DO SOMETHING ELSE. are you determined to make us wait till all our warranties expire so that you dont have to do ***?
This is a wothless fix! If you are reading this don't get your hopes up.