[*Unresolved* Issue] Alienware M18x: GTX 580M SLI DPC Latency Problems

UPDATE 02/21/2012: Please install Verde 295.73 drivers and implement the tweak posted here or here.

It is a rude awakening for anyone to discover that their Alienware flagship M18x beast is unsuitable for performing a task as ordinary as handling real time audio because of an unresolved driver bug. It's unfortunate that something correctable like this continues to be the Achilles heel of an otherwise incredible machine.

This thread was started for discussion of the DPC latency problem the M18x exhibits with GTX 580M SLI. I moved a number of my own posts into this thread to consolidate the information for Dell's benefit. Those are consolidated in the post below. If you're not familiar with DPC latency first hand, you don't want to be. You can read about it here. For me, this will usually manifest itself as strange clicks and pops in audio, and might be what causes what I like to refer to as the "cyborg" electronic distortion type of sound. I seem to get that randomly while gaming and sound sometimes ends up looping followed by a system freeze that coincides with that audio glitch. It does not happen all the time, but it happens enough that I don't forget about it.

It appears this issue does not affect systems equipped with AMD 6990M CrossFire. Additionally, DPC latency does not appear to be a problem running Dell's recommended driver (269.03).

Using Dell's NVIDIA 269.03 driver is OK with me for the moment, but it is starting to get a little long in the tooth and we cannot keep using it forever. We need to know what is causing it and how to fix it. Is it something Dell tweaked to correct the problem with their 269.03 driver, or is the DPC latency being caused by something NVIDIA changed in drivers released following version 269.03? Hopefully, Dell/Alienware can shed some light on this for us and produce a solution. If the reason is not known at the present time, then we can include this as an agenda item on the next conference call.

Here's where the assistance of the Alienware M18x Community is needed...

Before we can expect a fix, it needs to be established that an issue exists that needs to be fixed. If you own an M18x with GTX 580M SLI, please download LatencyMon from the Resplendence web site, run the test for 3 to 5 minutes and see if your test results are similar to mine. Please post your results and specify what driver you have installed.

When posting screen shots, please be mindful of forum rules. Images that are too large will be removed, and posts that don't make any sense without the image to reference will be deleted. Please use thumbnails or spoilers, upload the image as an attachment, or resize the image.

Thanks in advance for your testing and reporting.

 

I ran through a series of tests and the GTX 580M SLI setup has zero problems with DPC latency while using the Dell 269.03 display driver. The image below is at system idle when using the Dell 269.03 driver. I continued allowing LatencyMon to run and finally shut it off at 45 minutes. I never once had a spike.

I've checked this like 5 times now over the course of a couple weeks and every driver except Dell's is off the charts with DPC latency. (The Dell NVIDIA beta does poorly, too.)

 

You are absolutely on to something. I have also noticed this problem for some time and have the same results.


Sent from my iPad 2

 

Yep I have it too, although I wasn't even aware of it until I read it. =p

 

Please post screen shots of LatencyMon showing the problem (compliant sized images) and a short note indicating which driver you are using.

What prompted me to change my mind and go back to Dell's driver was issues with games crashing/freezing. I'm going to test the Dell drivers further to see if it helps with that. I did not perceive any issue from the DPC latency originally, but I may have concluded that in haste. I think these two things are related because the freezing is usually preceded by a stuck audio loop for 1 or 2 seconds. This does not happen daily, but it happens randomly more than enough for me to want this issue fixed.

 

I'll run the check in a few minutes after I get done installing arkham city. Do we need to make sure nothing is running in the background before doing the test? I think I read somewhere that if the CPU is active the dpc latency goes down?


Edit: Ok its just what I thought. When I have the nvidia control panel open with an active 3D nvidia logo, the DPC latency drops WAY down to normal levels. So as long as it drops during 3D gaming, I don't really care what it does in 2D. See attached photo.

Driver used: 290.36 beta

 

Here's my results on 6990Ms with Wi-Fi on (bad latency), and with Wi-Fi off (good latency)

 

Latency Issues here too, with my 580sli system & Nvidia Drivers.

Spoiler

EDIT:

I too noticed exactly the same as Joker - with the CP open, latency remains at or around sub 200....

Spoiler

 

Can someone run it in th ebackground on a 2nd monitor with a game running on the primary?

 

Just done that - other way around though. Game on my external and monitored on the laptop internal. Played Crysis 2 for a litte bit and latency seemed to hover within limits around 200us. After gaming for 5-10mins, and monitoring from the outset, the message was that my system was good to handle real time audio etc.

I repeated the process so the game was on the internal whilst I had the monitor on the external with extended display. Same result, all seemd ok to me.

 

Thanks for the testing, guys. You can run a 3DMark11 in a window and see the same thing... DPC latency drops like a rock running 3D gaming and benchmark applications. The latency issue might not be a problem in 3D gaming as long as DPC latency remains low at all times during gameplay and never has random spikes that screws things up... if it is stable in 3D gaming, this is a very good thing.

But, what about simple audio playback where the GPU is not under load?

This screen shot is with the Dell Recommended 269.03 driver... what happens with DPC latency in audio playback testing with Verde 285.79 or 290.36 reference drivers?

Spoiler

 

Good points, as usual, Mr. Fox. The M18x isnt just for gamers but audiophiles too, who may wish to do high end work without latency problems. Anyway, short test from me with the 290.36 drivers......looked relatively ok although I believe that under 200us is pretty much a stock requirement for pro-audio work.....

Spoiler

 

Hmm. I use mine for recording music, mixing etc, so this could be a pretty serious issue with me on my 580M rig! WIll have to do more testing when it arrives on Friday.

 

Hi, this is my test screenshots on audio playback and browsing.
Driver: 285.62 verde driver from nvidia website

Seems latency issues occur both when audio playback and normal use.

 

Going to do a clean install of the new Verde 290.53 Beta to see if it helps. I've also noticed that when a video or game is being played the latency drops. I'm not an expert on this subject by any means. I don't think the DPC latency should be high at an idle. I wonder if SLI being enable/disabled changes anything?

 

I think it a power Issue.

 

Please explain what you mean by "power issue" and why you think this to be the case.

 

Issue is still present with Verde 290.53 beta driver.

I just tested with SLI disabled, SLI enabled and SLI with NVIDIA Control Panel open.

Spoiler

SLI Disabled

​

SLI Enabled

​

SLI with NVIDIA Control Panel open

It would be nice to know what is different on the Dell driver that allows it to work properly... meaning, did Dell intentionally tweak something to fix this DPC latency issue in their 269.03 driver, or did NVIDIA simply break something in all of the later driver releases?

With the Dell 269.03 driver, the NVIDIA kernel mode driver does not even show up in the LatencyMon utility, so something is definitely different.

Spoiler

 

Hay fox.
Do you remember when the m17xr1 was having the DPC latency problem?., and AMD release the 4870M.....

 

I think i Red an article on google the mention it.

 

Ok fox chek this forum.

GTX 480 - High DPC Latency. - NVIDIA Forums - Page 2

 

I see some similarities, but not sure what you read about it being a power issue. However, I do appreciate the link. I posted on that forum and sent a link to ManuelG (NVIDIA Technical Support Group) and asked that he look at this thread and let us know if NVIDIA has a solution, or if they are working on one.

 

that is great, brother fox.!!!

 

bump bump bump!!! This is the only annoying bug left!! Is there anything I or anyone else can do to get this problem addressed/resolved?

 

I don't Pay too much attention to the DPC thing.

 

So far dpc has not been an issue for me in any game or application. Will continue to keep an eye out though.

Sent from my GT-N7000 using Tapatalk

 

I installed a program called fruit loops because my friend asked me too. My friend could see where the latency problem caused hiccups in audio reproduction that could be seen by the programs tools. He deemed my system unfit for audio sampling software.

 

While DPC latency may not cause an issue with benchmarks and games, it is definitely a problem with the NVIDIA cards (not just a Dell/Alienware problem based on what I see on the web) that needs to be fixed. Having a limitation to using the M18x for something as mundane and fundamental as audio sampling is an unacceptable limitation and we need Dell/Alienware to work with NVIDIA to correct whatever is causing the problem on the M18x and other NVIDIA-powered high-performance laptops. The M18x was designed with gamers in mind, but it is powerful enough to be used as an audio/video content creation workstation if DPC latency were not an impediment. There is no reason for a technical problem like this to be ignored when it is probably a matter of a simple driver fix. (The fact that the Dell approved video driver has zero latency problems shows that NVIDIA can fix this if they want to.)

 

Exactly.
Has anyone heard word from Dell or Nvidia? I'm sure Bill would help us resolve our one last problem.


Sent from my iPad 2

 

Thanks all. For my notes go ahead and send me your service tag numbers via private message. I will then forward it on to the team.

 

Thanks Chris - out of interest, would it be worth me sending you my service tag? (I'm obviously not in "system capture" territory, being in the UK.....if its just for general info, I will quite happily send.) Let me know.

 

Thanks for sending the information on. I sent you the service tag info for your own notes.

I do think this is an "NVIDIA problem" when all is said and done, but Dell certainly has the muscle to get behind a push for fixing it. Also, we're interested in knowing if Dell did something to tweak the R308308 (269.03-Dell Recommended) driver on purpose to fix this problem. Is so, why can't NVIDIA do it for all drivers? (It seems to be a problem for multiple brands and different NVIDIA GPUs.) Is there anything we can do to tweak the NVIDIA drivers to correct the DPC latency?

 

Service tag sent. Thank you.

 

I remember the m17xR1 with the 280M has this DPC latency problem.lol the 4870M

 

Seeing as this is the last real problem plaguing the M18x, I think this thread deserves a sticky. Could a mod please sticky this thread until we resolve this problem?

Thank you.

 

bump bump bump!!!

 

PM sent to Chris....better late than never.

 

Cool, we need to get a solution. Lol

 

Lately I had a couple of bsod's using badaboom and out of sync audio editing. They called me from an email I submitted. They asked me to check for latency. I did. Now they say that the high latency is causing the video/audio delay and my bsod's while using the software....great
They recommended disabling sli and contacting the manufacturer.

Disabling sli fixes it but it also adds time to the decoding/encoding process, defeating the purpose of using badaboom that is made for Nvidia gpu's.



Sent from my iPad 2 on the toilet.

 

Does that only happen when using badaboom for audio editing, or other audio editing software as well?

 

I only have problems with badaboom(video) and fruit loops(audio).

 

Bump again.........

 

Waiting for a response from Dell and/or NVIDIA. Both have been contacted and links provided to this thread. It's clearly an NVIDIA issue that affects all brands. Other forums (including NVIDIA forums) have posts on the subject of DPC latency.

 

Thanks for the post. I don't think most users realize the problem. Once you start using video/audio software that is optimized for Nvidia's Cuda with SLI enabled, the dpc latency becomes apparent during video/audio playback

 

that is true

 

The only reason I use Badaboom which is optimized for Nvidia GPU's is because converting videos for my iPhone 4S and iPad 2's native format saves on batteries. If I play a different format other than mp4 my battery drains quickly on both devices.

With the latency I can see hiccups or out of sync audio during playback. With sli disabled there is no problem or if I run a movie in the background with sli enabled there is no problem. Running certain programs causes the latency to subside. Once you stop those programs the bad latency returns.
So the dpc latency needs to be fixed.



Sent from my iPad 2 on the toilet

 

Yes, we need to be on top of this problem.



Sent from my iPhone using Tapatalk

 

'gunner. Perhaps you might want to give the free trial of Nero Multimedia Platinum HD a try. It does an awesome job of MP4 conversion for mobile platforms. I've never had any issues with it like what you are describing with Badaboom, even with the DPC latency. (We still need the latency fixed, but maybe this will work better for you while the DPC latency remains not fixed.)

 

I just downloaded the full retail version. I hate trials...lol. Plus Nero Multimedia Platinum HD is free everywhere Does Nero support SLI/Cuda like Badaboom? In the meantime I'll install it and give it a go. Thank you......man Nero keeps getting bigger and bigger. That download was 1.2gigs.

Even so, The DPC latency problem still needs to be resolved.

 

BUMP!

Just ran Resplendance latency monitor on my new system with Nvidia 290.53 drivers - same high latency problems

I hope this is something that Dell & Nvidia can address as it is very important.