This post is also over at Notebook Forums and Laptop Discussion here. My attachments are also located there regarding my screen shots and logs.
I've been reading about these three issues a lot on the forums lately. I've done several tests as well as several formats and installs. So far, I've encountered a very mild stutter with the very basic install of Windows 7 Ultimate 64 installed with stock drivers as well as Batboy's. I've also encountered lock ups, granted these have been far between, I've still had them. Most of them occurred on the normal desktop, loading up Firefox, scrolling down a website on Firefox, starting Steam, etc., one upon starting CoD MW 2 before I even clicked on anything it locked up. Sometimes I have a single program hang, then start working again after a few minutes. Windows will complain to me if I click on the window that it isn't responding, but normally I let it continue what it's doing.
I've taken logs of all my temperatures and some screen shots of the DPC latency spikes (shame I can't log that), and a majority of my issues seem to be occurring on the simple desktop, which IMO makes sense as I see my GTX280M's clock speeds change the most while on the desktop, while in game they tend to stay on full load. The minor stutter I encounter is definitely directly related to this issue as well, because my sound will stutter if I have something running in the background and I'll notice the slight jump of my mouse if I was moving it. I check the logs and the frequency certainly changed when I had the issue.
*ADDED* --The issue does still remain after using PowerMizer, as it only modifies my primary card and my secondary card remains untouched, possibly related again to my FurMark tests mentioned below.
Looking at the posts throughout these forums, nothing I've come across has worked, following links to several other websites and wandering through www.sevenforums.com, nothing. I've modified the "Available Memory" to 3990, installed sound/video drivers, uninstalled sound/video drivers, used Windows default sound drivers, nothing has stopped the DPC latency or the mild stutter.
Other steps I've taken have been to disable my 9400 through the BIOS, after-all, that could be it right? So I disabled integrated graphics and of course Hybrid SLI, first I tried simply turning of Hybrid SLI, no change, then both, again, no change, minus my screen doesn't blink black a few times after boot up.
That said, I pressed on, I did more benchmarks. In 3dMark Vantage I achieve around 8k on 186.64 (stock drivers) and 10k on Batboy's 186.82. Processor wise I'm not going to post those stats because I haven't run a proper test of it. Next I loaded up FurMark 1.7.0 and I noticed something very peculiar, something I had only just a few minutes earlier read about in a post on the Dell Community forums regarding a UK user's unfortunate experience with his M17x. The issue is that while running a Stability Test in FurMark, first with Hybrid SLI enabled, I noticed the temperature of only one card increasing, capping at 64~65 degrees, while the second card I have started at the same temperate of 37 degrees and only decreased as the temperature increased on the first card, down to 33 degrees. What this looks like to me is that the full load of FurMark was being placed on my first card, so how in the world do I fix that!?
I'm at a loss, tomorrow (Monday), I plan on contacting Dell and hopefully speaking to a knowledgeable tech who speaks English well enough to understand that I've done my homework, now I want the answers.
Anyone else here have any ideas? I honestly believe all of these issues are related. Just about everything matches the Video Card handling and the changes that are made to them throughout usage.
Also, I'd like to point out I have run tests with PhysX enabled and disabled, there is no 3d Stereoscopic Vision on my system, and I have tried disabling wifi, bluetooth, sound and zero change in average DPC history.
Aedaric